In a UK comic back in the sixties, there was some villain who looked like Gru (from Despicable Me), but he did a big grin sometimes, and then bats flew out his mouth.
Grimly Feendish was a supervillain who sought to conquer the world, using both his monsters and bizarre plot devices, such as exploding treacle, to do so. He was usually thwarted by Eagle-Eye, Junior Spy. At one point Grimly started Doomsday School for young monsters across the road from Eagle-Eye's school, Conker Crescent High. One of the students at Doomsday School was Grimly's nephew, Fred Feendish, who became friends with Eagle-Eye and would sometimes try to warn him of his uncle's schemes.
A Google search for "Gru british comic 1960's" turned up the info fairly easily.