* FetishRetardant: Later stories(especially after 1990s) made the main female characters like Reiko much bustier, and some readers got this reaction.
* HoYay: While the scenes in questions are always PlayedForLaughs, there are several moments where the characters get in homoerotic situations, usually involving nudity and Ryotsu displaying a NoSenseOfPersonalSpace.
* PeripheryDemographic: This shonen anime managed to capture the attention of fans of the BaraGenre by including plenty of nude scenes featuring unconventionally attractive male characters, some of which are borderline homoerotic.
* UglyCute: Ryotsu. Hairy monobrowed short guys shouldn't be so endearing.
* UnintentionalPeriodPiece: Because so many stories focused on the "new" things in then-current Japanese society, you can see this trope a lot. It's really noticeable when characters talk about the latest techs, like video game consoles or phones.