I Was Given the Role of a Demon

BEFORE READING! THIS NOVEL FOCUSES ON SMUT, WITH A SIDE DISH OF STORY, READ AT YOUR OWN VOLITION
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Daan D. Dickenson, A 21 year old NEET, lives in a world full of Super Heroes and Villains, his childhood friend made a live for herself as a Heroine, and his MILF landlord has been pestering him to pay rent.
One day, as he was walking through the local beach early in the morning, he spotted a drowning woman, when he tried to save her, the woman turned into a black goo and fused with him.
Hours later, he woke up in his apartment, when he saw a system notification:
[Congratulations! You have been chosen as one of the candidates for True Demon! You have been assigned the role: \"Demon(Lust)\", Good luck!]