Манамі

Manami was an anime only character. He was a young baby who, along with other babies at a nursery school, was targeted for energy by the Cardian Amaderasu. When his mother's energy was taken, leaving her hospitalized, he was taken in by Mamoru. Usagi attempted to help take care of him, and even though she was not very good at doing this, Manami enjoyed her company (as opposed to Natsumi Ginga, on whom he urinated twice in distress). He walked for the first time in Mamoru's house and his first words were "Mamoru-san, Usagi-chan, bye bye!". Due to his feminine name (which is written with the characters meaning "love" and "beauty") he was intially thought to be a girl.

(Source: Wikimoon)