I've wondered that too, but I respect their privacy :P
I think that hugging thing depends on their personality; Jessie's Mimikyu in the Anime was a blood thirsty killer, but Acerola's (although.. a dead ghost?) was fiercely obedient and loved her even from beyond.
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JanusMax
I've always wondered two things about Mimikyus. What do their actual selves look like and do they want hugs?