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Curry Contest Arc
Instead of finding Mina after the contest, he finds her beforehand, where she mocks him. This saddens him enough that he goes to sit by himself while the contest proceeds. Ciel approaches him while the judges deliberate, and ask him why he's not supporting Agni.
Reflecting on this, he decides to find Agni, but notices that Mina and many of the audience members are on a rampage from curry ma, a spice that makes people with darkness in their hearts go on the rampage. During this time, Angi and Soma make up, and Soma orders Agni to stop Mina. He also tries to help, even blocking Queen Victoria with his own body, which ends up being unnecessary when Mina slips on a bit of lobster. Sebastian then force-feeds her and the others the cure, his curry bread. It is implied that, after this, Soma and Agni return to India.
Conspiracy and Revenge Arc
Soma does not show up again until after the fire in London has been put out. He then returns to London with Agni and hands out curry buns to those affected by the fire.
He appears in the second anime season where he is seen with Agni continuing to hand out curry bread to the poor. One day, Sebastian approaches him and tells him that Ciel has been wiped of all his memories of what happened in the past year. He is clearly devastated but agrees to not mention anything about it and to not act strangely when around him. He goes to the costume party hosted by Alois Trancy and upon seeing Ciel, he is unable to stop himself from rushing over to hug him whilst crying sad tears and Agni is barely able to stop him from messing up the plan. In the costume party at Alois Trancy's mansion, he dresses up as Sherlock Holmes.
He is last seen in the very last episode when Sebastian visits him and hands him a farewell present from Ciel. He learns that Ciel has supposedly "died."