Raichi is Ichigo's little brother. He is obsessed with Mizuki Kanzaki, influencing Ichigo to become a fan herself. Raichi had a collection of Mizuki's photographs but was accidentally damaged by Ichigo. He helps his mother run a bento shop. He also admires Aoi Kiriya. His name probably alludes to the lychee fruit, considering the fruit theme in the family names and the L on his shirt.
(Source: Aikatsu! Wiki)