When you look at a girl that's kinda cute but kinda not and you don't know if you would have sex with her so you're gonna debate it in your head first.
A quality that one can only wish to possess. It is a very desirable genetic trait and is typically used for the opposite sex. The opposite of debeastable would be someone that shows shithead tendencies.
"Dan Engerim(sp?) is very debeastable because he works in the student store..."
"Mary is such ashithead, she is like the furthest away from being debeastable."