More a human mascot than a full-fledged character, Takeda is a phallic caricature (literally) of an awkward horny early teenage boy, the only character always drawn deformed, and the primary generalist pervert. While other boys (and girls) list certain deviancies among other traits, he is the walking embodiment of a pervert, and his varied perversions are his only trait.
In the few scenes where he isn't leering, peeping, fapping, taking voyeur pics, groping, or ineptly trying to pick girls up, other character's disbelief that he is actually doing something normal is a common source of comic relief.