1. A man who prematurely ejaculates 10 out of 10 times.

2. A man who's dick is incapable of holding in his baby liquid.

A Bloomer is someone with a bright outlook on life who is optimistic in nature. Bloomer's frolic in every opportunity to be happy and try to make the most out of life. The opposite of a Bloomer is a Doomer. The term Bloomer originated specifically as a counter to the Doomer on sites especially like 4Chan.