When Kush was six, he walked in on an argument between his mother and father. Carmel was clearing out Umar's pocket and found a packet of condoms, discovering he was having an affair. He yells at Kush and hits Kush repeatable, Kush ran to his room and put all his toys up against his door.
He was previously married to Safirah on 13 June 2012. On their honeymoon, Kush got a tattoo with the date they got married in Roman Numerals (XIII VI MMXII, 13/06/2012).
Not long after Kush and Safirah got back from their honeymoon, Kush was playing a five a side football competition, he went to get changed after the game and had three missed calls on his mobile, from Safirah. Kush thought she'd just changed her mind about what she wanted to eat that night.
When he rang her phone back it was her boss that was calling him, Safirah had collapsed at work and they'd called an ambulance. Safirah's boss told Kush it was a pulmonary embolism (a blood clot on the lung) and he said to meet them at the hospital.
Unfortunately there was heavy traffic on the road, by the time Kush got there Safirah had died. Kush never got the chance to say goodbye.
After Safirah's death, Kush then moved back with his parents. Kush spent the next year going to bars and having sex with strangers. Kush realised he couldn't live in the past anymore, he moved to Walford and got a new job as a market trader, where he met Shabnam, and started a relationship with her.
Kush made his first appearance on 20 October 2014. He is a friend of Martin Fowler. The character and casting were announced on 19 August 2014, when it was said the character was a "good guy" who is "funny and full of energy". He is said to have a "brash exterior" underneath which hides "a tragic past that he is keen to escape from". Ghadami said of his casting, "I'm so excited to be joining the cast of EastEnders as I've been a fan of the show for as long as I can remember.
Kush causes disruption on his first day by trying to drive his van down Bridge Street, but ultimately makes friends due his casual nature. He is attracted to Shabnam Masood, despite her coy nature, and helps with the cooking for her brother Tamwar's birthday to impress her. Kush helps Martin's wife Sonia Fowler to arrange a nude charity calendar, convincing her by walking naked through the market. As they bond over the idea, Sonia attempts to kiss him, and then admits that she is having trouble in her marriage. Kush encourages her to forget about it, and later takes part in the charity calendar along with Sonia. In an attempt to give Shabnam some Christmas spirit, he kisses her, but keeps this from his friends. Kush pushes Shabnam on her feelings for him, and she later has a one-night stand with him as she is upset over losing her job. She rejects him after, feeling guilty for betraying her religious views, until Kush convinces her to start a relationship. They keep it a secret, until Stacey Branning rumbles them and they decide to tell Shabnam's family. However, Shabnam's father (Masood Ahmed) hears it from Donna Yates first, and is angry at them for keeping it a secret. Shabnam persuades Masood to accept them but ends up lying that Kush has proposed to her. When Kush tells her that it is happening too fast, because they have only been dating a short while, Shabnam is devastated at her actions and Masood throws him out. Afterwards, Kush confides in his friend Martin Fowler that he is not ready for another marriage after the death of his first wife, Safirah. At Donna's 30th birthday party, he gets drunk and when Shabnam tries to talk to him, he tells her that he is still grieving over the loss of his wife. Eventually, Shabnam admits that she does not want to get married—she only lied about the proposal because she loves him. They decide to take things slower. Masood comes round to this, but tells them that he does not want to see Shabnam getting heartbroken.
After kissing Stacey a second time and regretting it, Kush finds out that Shabnam is five months pregnant with their child. He has initial doubts about his future with a baby, but apologises to Shabnam and tells her he wants the baby and they begin planning their wedding. Seven months into her pregnancy, Shabnam's baby dies, leaving Kush heartbroken. Shabnam gives birth to their son, Zaair, but Kush is unable to cope and leaves the room. Later, he does visits Zaair, cuddling him and telling him how proud he is. Shabnam and Kush argue because he was not there for her and she plans to move to Pakistan, while he considers returning to Essex with Carmel. However, Carmel and Masood get them to reunite. Shabnam rearranges their wedding, hoping that being married will help them gain custody of her daughter Jade Green. Kush thinks they are marrying for the wrong reasons but they agree that they love each other and want to marry. After the wedding, Shabnam tells Kush that Stacey's baby is not Martin's, and Stacey tells him she thinks he is the father. Stacey swears him to secrecy and he marries Shabnam before departing on their honeymoon. When they return, Kush learns that Shabnam took Jade without permission. They decide not to go for custody when they realise they have not come to terms with Zaair's death.
When Stacey's son, Arthur Fowler, is born, Shabnam this Kush could be the father due to his behaviour. Shabnam confronts Stacey, worried she will lose her husband, but Stacey tells her he is not the father. However, Shabnam later hears Kush and Carmel talking about Arthur being his son, and Shabnam begins to re-evaluate her marriage. She wants to tell Martin the truth about Arthur's paternity, however, Stacey's mental condition worsens and she and Kush agree to wait, Kush vows to prioritise Shabnam over Arthur. Kush suggest that he and Shabnam move away, but she decides to leave on her own, urging Kush to stay for Arthur. Masood finds out about this and Arthur's paternity, he punches Kush and threatens to kill him if he comes near Shabnam again. He tells Kush that Shabnam has already decided to leave Walford. Kush then breaks down in Carmel's arms, thinking he has lost Shabnam for good. Despite his pleas, Shabnam leaves Walford with Jade after planting a tree in Zaair's memory, telling Kush they must lead separate lives, but still loves him. Kush starts drinking heavily and Martin finds out Kush is Arthur's father. Stacey tells Kush he can be part of Arthur's life, but Martin disagrees and breaks his friendship with Kush. An emotional Kush has sex with Nancy Carter, who has an epileptic fit in his bed. Kush calls Nancy's former boyfriend, Tamwar, who calls Kush selfish. Kush realises he is a bad role model, so tells Stacey and Martin that he wants nothing to do with Arthur. Tamwar calls Carmel, who agrees to move in with Kush. She then reveals that his father has sold their house and she is homeless.
Kush develops feelings for Carmel's best friend, Denise Fox. They admit their feelings to each other and they have a brief fling, however, she ends it, fearing it will ruin her friendship with Carmel. Kush later discovers, from Carmel, that Denise is pregnant and believes he is the father, but Denise tells him he is not as she is eighteen to nineteen weeks pregnant. Kush later advises his younger brother, Shakil Kazemi, when he wants to have sex with hi girlfriend, Bex Fowler. When the explicit image Shakil sent to Bex goes viral around Shakil's school, Bex is blamed, even though Louise Mitchell sent it. This causes things to become fraught yet again between the Kamzeis and the Fowlers.
Kush pursues Denise again, but she turns him down due to her friendship with Carmel. After having a drink with Denise, Kush is in the fish and chip shop when Michelle Fowler crashes into it, leaving him unconscious. Denise helps rescue Kush, and while he is in hospital she admits her feelings for him, they start a relationship. Back home, Carmel interrupts Kush and Denise on morning, but assumes that Kush has met a doctor from the hospital, which he confirms. Denise tells Kush they should admit to their relationship from the start, so they tell Carmel, who is shocked, telling them that when it ends she will side with Kush and lose her friend forever. Kush asks Denise to move in with him but she declines, Kush accusses her of comparing him to her controlling ex-husband, Owen Turner. Kush storms off and goes into cardiac arrest in the middle of the market, he is diagnosed with Brugada Syndrom. Denise regrets rejecting him and spontaneously proposes to him in the hospital; he accepts. Later, Kush's brother, Darius Kazemi, offers him work in Dubai, but Kush and Carmel are left devastated when Shakil dies after being stabbed by a gang.
When Kush and Denise end their relationship, he begins having a secret sexual relationship with Kat Slater. The pair decide on secrecy due to the complicated relationship Kush has with the Slaters and Fowlers, but are caught having sex and come clean. Kush witnesses Whitney Dean being harassed by Leo King on the balcony. Rushing to her defence, he accidentally pushes Leo over the balcony.