Tamama

He is a Private Second Class, which makes him the lowest-ranked officer on the platoon in addition to being the youngest. Rather than focusing on personality traits from the original source materials, a large emphasis is placed on his hyperactivity, randomness, and often downright stupidity.

History of Characterization
His debut in Episode 0 focused mostly on his homosexuality, though there wasn't any other quirks to him to make him seem particularly special, as he just seemed to perfectly normal otherwise. At some point when writing for the series (some time before MontHenryKnitly came onboard), RabidSonicFan decided that it would be much funnier if Tamama were just a complete moron, sputtering random and [very often] nonscenical phrases. Since then, Tamama's personality has never changed from this depiction.

Relationships
Keroro -Tamama has a man-crush on Keroro (though this is toned down a bit to moreso focus on his stupidity). Keroro seems to be aware of this, but he doesn't really seem to care and ignores his advances. Other than this, though, they seem to have a fairly good relationship, despite their vast differences in intelligence. Because of this, Tamama has more of a relationship with Keroro than any of the other characters (even Momoka), interacting with him the most.

Kululu - They don't seem to have much of a relationship either, though they sometimes suggest that they're attracted to one another (particularly in the introductions for Angol Mois and Taruru).

Momoka - Tamama lives with Momoka, in her mansion, but this is only really touched upon in a single episode. In spite of this, they don't really interact with each other very often, but they're seemingly on good terms (in the aformentioned episode, anyway).

Angol Mois - In Mois' debut, he is insanely jealous of her relationship with Keroro, like in the original series (though now, it's even more irrational, seeing as Keroro and Mois are now related by blood) and went at great lengths to stop her from getting close to him. Though since then, he hasn't had any sort of interaction with her.