Hoshi, a 24-year-old resident of the riverside village, always wears a star-shaped mask. The Village Chief gave him his name, meaning "star" in Japanese. Before living under the bridge, he was a famous musician whose songs frequently topped the charts, but he abandoned that mainstream career four years ago due to creative differences; his management rejected his original compositions. Meeting Nino, a resident claiming to be from Venus, coincided with his departure, and he joined the village to pursue creating his own music independently.

Under the star mask lies a secondary moon mask, concealing his actual face, which features red hair. During depressive episodes, he calls himself a "starfish," wears his star mask backwards, and frequently visits a nearby convenience store to buy cigarettes. His astrological sign is Taurus.

In the village, he performs music during special events, though his lyrics are typically nonsensical and unconventional. Strong romantic feelings for Nino motivated his move to the riverside. This unrequited affection fuels a persistent rivalry with Kou Ichinomiya (known as "Recruit" or "Ric"), another resident who becomes Nino's romantic partner; Hoshi actively attempts to disrupt their dates and undermine their relationship.

Nino largely remains oblivious to Hoshi's romantic gestures and affections, yet readily notices and responds positively to similar actions from Kou. This selective attention reinforces Hoshi's jealousy and competitive behavior toward Kou. His personality blends artistic passion with persistent melancholy, evident in his unfulfilled romantic pursuits and depressive "starfish" episodes.