Even though Miyumi is biologically male, his name translates into "beautiful"(Reference to his gorgeous looks) and "archery bow"(Reference to how straight forward he is with his childhood friend when he sees something "off" about him). 
Miyumi is vocal/mental autistic but he is still loved by fangirls/fanboys but most of all, his family and his true best friend(childhood friend)

Miyumi is gay but he doesn't understand the meaning of it until he slowly learns about love relationships with his BF