My cat Lucky is a suckeler too. When he's in the mood, usually at night or when we are laying down watching TV, he sucks on our earlobes or the "chubby part" of our hand skin and kneads and purrs with his eyes closed. It's cute at first but the purring in the ear and sucking on the earlobe is very ticklish when we're trying to sleep! Our routine is every morning when I sit in the sink to do my makeup, he waits for me and then gets in my lap and hugs my hand and sucks on it till he falls asleep, it's so cute.

Here is a picture of him suckeling Daddy's hand in bed one morning:



We think he does this because he was separated from his mom early, he was found alone about to cross a highway at 7 weeks old!