Looking for story, dad son nonconsent

[Curiousity69]

I once read a story about a guy used to be coach get raped by two guys and then he thinks one of them was his son so he decided that he's gonna get fucked by him again. Turns out it was not his son who raped him. But he already liked it.
Can anybody help me, i've been searching but i don't know the tag and the category on it. Thank you