underover achiever 

a person who has the appearance of an over achiever, but is NOT!

Jessica is an underover achiever, because she has yet to finish a task this year.

underover achiever by hflaglerra October 31, 2009

under over acheiver 

its that One person u know who does dick all but has fucking amazing things happen to him/her consistently.

Calvin is a under over acheiver and always high but for sum reason is a pussy magenet with a 70 sum average

under over acheiver by BluntTrama January 11, 2010