Zsa Zsa and Leon both leave, but separately, leaving Mercy and Fatboy upset at the loss of their friends. At a New Year's Eve party, Mercy kisses Fatboy to put Kim Fox (Tameka Empson) off flirting with him. As the party continues, Fatboy cuts his finger and Kim starts to crawl along the bar offering to kiss him. Enraged by this, Mercy walks over and pushes Kim off the bar onto the floor below. She takes a liking to Seb Parker (Tommy Bastow), which leaves Fatboy jealous, and later he accuses them of having sex, to which Mercy does not reply. She then reveals she may face deportation as she only has a Nigerian passport and her visa has expired but she has lived in the United Kingdom since the age of nine. When Fatboy mentions this to his father Ashley Chubb (Colin Mace), Ashley reports Mercy to the UK Border Agency. Seb ends his relationship with Mercy, and then she is approached by Daniel Mansard (Richard Galazka) from the Agency, saying she is four months past her permit. She decides to leave the country before she has been asked to and says an emotional goodbye to Fatboy, but as he sees her saying goodbye to Grace and leaving in a taxi, he stops the car and asks Mercy to marry him. Mercy agrees in the hope she will stay in the country. Mercy confides in her friend Lauren Branning (Jacqueline Jossa) that the wedding is a sham. She later says she is worried about going to court as she feels she is being treated like a criminal. On the morning of the wedding, Mercy feels guilty when everyone comments on how much she loves Fatboy. She tells Lauren that she wants to do the right thing, and there will be no wedding. However, they do marry, and Mercy soon learns that she is able to stay in the country. However, she feels guilty about what has happened and decides to go to Nigeria anyway. She tries to tell Fatboy but eventually decides to leave without telling him. However, he finds out and tries to stop her. They say an emotional farewell before she leaves in a black cab. Mercy's sister Faith (Modupe Adeyeye) later arrives in Walford to tell Fatboy that Mercy has had the marriage annulled. Mercy is one of four characters created by a team of 13 writers aged between 17 and 22 for the Internet spin-off series "EastEnders: E20".