This plot sounds very similar to College Boys by Daisy Harris, but I liked that so I don't mind reading a variation of it. I can guess the twist Tasha was actually the other masturbater but still it looks cute.
I hope this series comes out in a bundle, dunno if I want to spend $2.99 on each (although #1, [b:Hot Hands|18167889|Hot Hands (College Fun and Gays, # 1)|Erica Pike|http://d.gr-assets.com/books/1373218609s/18167889.jpg|18611980], was really good and FREE at All Romance eBooks).