noun
sissy; effeminate boy
Wasei-eigo term for a boy or man perceived as effeminate or unmanly; can carry a derogatory or mocking tone. Not a direct translation of English 'sister boy'.
wasei-eigo (Japanese-coined English), from sister boy
彼はクラスメートからシスターボーイとからかわれた。
He was teased by his classmates and called a sissy.
あのシスターボーイはいつも女の子みたいな
That sissy always wears clothes like a girl.