「まあ、どうせ紫のとこだろうなー。
　きっと今頃乳でも揉みしだいてるんだろうな。
　あいつの紫好きにも全く困ったもんだぜ。
　あの愛情をちょっとでも私に向けてくれれば…
　い、いや、まああれはちょっと熱烈すぎるから
　今のままでも良いか…
　しかし、もし私の勘が当たってるとしたら
　放置してると紫の貞操が危ないよな。
　よし、探しに行こう。」

ピンポイントな魔女の勘。

"Ah, she's probably off at Yukari's place...
She probably went over to feel her up.
Geez, Reimu's love is really troublesome.
If she were to direct some of that love toward me...
... O-on second thought, that would be a bit too passionate...
The way it is now is fine...
But if my intuition about why she went over to Yukari's is right,
then her chastity is in danger, isn't it?
Well, better go look for her, then."

A witch's intuition is spot-on.