A boy, typically wears a sweater (sometimes argyle on special occasions). Enjoys rubber fists and other related paraphernalia. Ejaculates in a disturbingly short time, sometimes bragging about his inability to hold his load. Almost always used in a negative connotation.
Wow, his birthday is July 18th!? What a baby buns!
I can't believe that guy came out of the bathroom in 1:30 with his gf, what a baby buns!