1) -YUGAAAAAH! -DEIBU'Z EYEEEE! -...yu? 2) -Reimuuuu! -ICH HUUURCH! ICH HUUURCH! 3) -Reimu! Reimu, I'm sorry! I didn't do it on purpose! -If I did it on purpose I'd get the judge-ment from the rest of the tribe, so I didn't do it on purpose! I'm sorry my peni-peni is so hard! 4) -Yuhooooow daaare you how dare you Reimu's cute eye! -Kind Reimu told you to drop dead, but I was planning to forgive you after some wordplay! 5) -I am now completely -pissed!
Well it would be PostItEase if she wasn't lying to her partner who seems to really want to have babies, just think of it like this, imagine you want to have baby, your first one, yet each time you do it with your partner, nothing happens, you worry about your capacity, your partner's , etc. Then you find ous that your partner was using contraceptive without telling you only for the sake of the pleasure, you would feel betrayed and angry.
It doesn't help that the mushrooms seems to mess up a bit Marisa's psycology and won't wear off quickly enough for "when they aren't in the mood anymore".