The Parasitological Museum of Meguro
It's not the best place to take a date, nor would you want to visit after eating a large meal, but the Parasitological Museum in Meguro makes a wonderful excursion for when you... I mean, it's fun if you're in the mood for... Or, it's interesting for those who... You know what? I'm drawing a blank. I can't think of a single non-creepy reason to visit the Parasaitological Museum. Unless you're a professional parasitologist. (Even then, the very fact that you're a parasitologist is kind of creepy.)