*rides in from the distance, forces open the doors and storms into the room* "Comrades! Comrades! I bring news from the East. A Bifidus book will be released in Japan on this day. Our hope is not lost"
Ah, sweet Vanilla Osananajimi.
"When your spring comes along, and you find the girl of your dreams, will you stop coming"? The perfect answer to that would have been "I'll still keep coming over because spring is here and you're the girl of my dreams"...Or something like that. I certainly think a development like that would've been interesting, but I'm happy enough with what we got.
Great ending though. I wonder if she's actually just feigning ignorance...?
Alternately, Mom could have firmly recommended that, when they *cough-cough* "do it", they use protection, at least until they both graduate ... and not rely on the 'withdrawal method' ... or something like that.