A guy who may look like an intimidating strong hottie on the outside. Very macho, but on the inside he is a giggly lil kiddy all full of lovey doveys, usually only a girlfriend can see this special side of him.
"That guy seems so serious!" "No way, we've been dating for over a year now, he's the biggest snugglebutt you'll ever meet."
In essence, a 'snugglebum' is a human heater. It is the guy/girl that you can cuddle with on a cold/rainy day without any sexual tension between you. It is when two people (who are madly in love) snuggle together all day instead of getting up and doing things that need to be done, (like chores, errands, homework, even socializing with friends, cleaning, etc). It can be used as a term of endearment as well and although this may seem to be emasculating, it is not. The boyfriend (or soon to be boyfriend) will usually want to go do something else and he may even get bored with this mundane task of cuddliness but if he loves his girlfriend enough he will lay down with her and be called a 'snugglebum'.
Michael: "It's raining out, what do you want to do?"
Amy: "I'm not sure, it's kinda cold..."
Michael: "Do you want to lie around cuddling all day?"
Amy: "Yup, let's watch a movie and snuggle!"
Michael: "fine....we'll be snugglebums"
An opportunity in which to snuggle. When your girl is alone and ready for snuggling that is a snuggletunity. You never want to pass up a snuggletunity. Netflix and chill is a perfect snuggletunity.
My girl was home alone in cute lingerie and said to come over, I couldn't pass up that snuggletunity