Is that a marathon per year, or a buttfuck per year?
How long is a marathon, and how can you have several per day? Wouldn't it just be one marathon, then?
Sorry for not clarifying. It's a buttfuck per year, which would equal to a marathon of buttfucks. Or, you can just make it a continuous, last-man standing buttfucking event.
I dunno...you've already done the whole "opening a box and there are tentacles inside" thing.
What about a birthday demon summoning with huge birthday anal destruction?
I guess you could always go with the whole birthday orgy thing, but I'm sure that was already suggested, so maybe it could be like all her friends giving her sex toys for presents but I know your not a fan of dildos. Hmm maybe you could have her decorating her cake with semen, or instead of blowing out candles she has to blow the dicks?
Ow ...
How long is a marathon, and how can you have several per day? Wouldn't it just be one marathon, then?
or what
What about a birthday demon summoning with huge birthday anal destruction?