a mini comic for my awesome friend RioluMaster237 of one of his characters Nitro, and as you see here that dark red spiky fruit is known as the beastial fruit which holds very corrupted power of the dark beast and those who dare to eat these will succumb to the beastial's power as the energy infects the body from within changing and altering their body including their personality and soon enough wound up becoming a monstrous dark beast, and now here's Nitro eating a beastial fruit but not aware of the its corrupting power until he actually notice the sudden change but it was already too late as Nitro fully change into a dark beast!

and also he's not that dark in the last panel it's more of a silhouette of what he looks like now after eating the beastial fruit.