I'm a boy !

Mori-kun was very often referred as a "school girl on rooftops" because of his appearance. As we all know, Morita had let his hair grow long and he wears a girl's sailor outfit. His attitude, however is still devastating. 

He was caught several times walking on houses' rooftops, sometimes climbing fences to reach the roof easily so he could escape anyone trying to get him. One day he had be caught by shop owner trying to get on top of the front sign. The dialogue that ensued was literally this:

"Hey young girl, what are you doing up there !? Get down !"

"No I'm not !!"

"I will not hesitate to call the police if you refuse to come down !!"

"I will run away ! And I'm not a girl !"

The shop owner looked at Mori-kun and he wasn't convinced. Mori was fairly high up there and his voice couldn't be heard very clear down below so he sounded high pitched and distant. 

Mori then jumped on the roof but he slipped and he caught the gutter, he realized he had to come down because the roof slope was steep and he couldn't get up. He went down and the shop owner had caught him. He questioned Morita about what he said before jumping:

"What do you mean by "I'm not a girl ?" you clearly are, from your looks !"

Mori became irritated and he decided, out of nowhere to pull his collar down and simply say:

"I'm a boy !"

No other explanation was needed as why he wanted to show his chest to prove he's indeed a boy but the shop owner was left speechless as he wasn't expecting nor Morita's gender nor his reaction. He went back in his shop and smashed some watermelons into a glass so he could drink and forget about this weird encounter. Morita, on the other hand walked away and as he went out of sight, he climbed another building.