Strappleberry is an Ungodly Abomonation that was actually used by the Wrigley company in actual ads in the real world.
Strappleberry was spliced together painfully from apples and strawberries. Each breath it takes is agony. It lives pain, and knows nothing but suffering. Strappleberry has lived for so long in the Mysterious Yellow Dimension in constant insurmountable pain that it became enlightened. He used his wisdom to aid Koopa's escape from the Yellow Dimesnion. Koopa had to do this by besting Strappleberry in word puzzles involving pain onomatopoeia. So since he was an opponent of Koopa, I guess he's an enemy. it is currently unknown if he and Grapermelon are alive, but it might be better for them if they weren't.