Takeda Seito is a regular supporting character in the series Umisho. He is in many respects almost a stereotypical anime-manga teen boy, actively scheming to see his female teammates naked and more, to gain some sort of power over them, even by devious means. The sad part is, he is intelligent, a decent swimmer and is able to come through in a major way when focused, but this focus invariably gets lost in a maze of hormones and ego. His look, it should be noted, is not meant to show him as truly ugly, but rather, it is the mangaka's way of showing a boy of average looks, as opposed to a bishonen like Okiura Kaname.
Takeda is shown throughout the series as being able to snatch defeat from the jaws of victory, a greater fool than if he were merely stupid.
The first such incident came when the houseboat of his teammate Ninagawa Amuro came loose at sea - an incident where he could easily have proven himself. When the girls onboard turned to him as the only male available, he began to bark abusive orders and ended up being a prime cause of the houseboat breaking apart. He was quickly clobbered and dismissed as useless by team captain Orizuka Momoko. He was also a master of making useless 'ecchi' suggestions towards the girls when serious ideas were called for, ones he had to realize would be brushed aside, and which only made him look all the more foolish. When Orizuka graduated and left as team captain, it seemed like a more serious side of Takeda emerged as he made what looked like a sincere bid to defeat Kaname in the team election to replace her. Kaname quickly realized, though, that Takeda's sudden rise in the pre-election count was the result of extortion of embarrassing secrets Takeda had recorded on his digital camera by stalking his victims. A rally of the ladies' courage led by Kaname made certain that one vote overturned Takeda's bid, which he had pushed his luck on anyway by absurd demands such as co-ed changing areas. Takeda then also lost his camera and suffered the predictable wrath of his targets. Probably only the team's desperate need for any decent swimmers kept him from being banished entirely. He was allowed to stay, but an eye was kept on him, and some girls confessed the secrets he had on them anyway just to be sure he never pulled this stunt again.
In the finale, Kaname revealed that history had repeated itself for Takeda, who had founded a successful capital venture start-up firm, only to destroy his position through rantings on a blog. Full maturity seems not an option for him, and more's the pity.