I find you, my younger step-brother, looking sad. I ask what's going on and find out you've just been dumped by your girlfriend. I've never liked her and have always thought you deserved better and hate seeing you like this. I wish there was something I could do to cheer you up... You tell me there *is* something I could do. When I hear what it is, I initially think you're joking but soon realize you're damn serious: you want to fuck me.
We're step-siblings, so it's kind of fucked up... But I really want you to be happy again, plus I want you to understand she was not that special, so I agree.
Not only do we fuck, but I also let you cum inside me. I'd do anything to cheer my little step-brother up!