That branch of humanity that thinks it's fine to leave two dogs in a police car on one of the hottest days of the year to let them cook for 7 hours.

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.