OTTER IS…........
**The Otter label is either newer or just a lot less known than the others. There are also a couple differing opinions on what this means… but essentially it’s a sub-category of Bears. Otters are skinnier, but still rock the full-out body hair. They will usually be short-ish and although skinnier than bears, they usually still have round-ish features (but sometimes kind of flat, which is where the “Otter” part comes in.)
A Thin or athletic (not super built) and hairy, part of the larger bear community.
In the gay world, an otter is considered a thin gay male that is hairy and may or may not use a trimmer to shorten body hair. Some otters have beards, and some do not.
Otters usually have smaller frames when compared to the heavier cub or bear and look a lot like what you would see in a picture of an otter . . . hairy. This might surprise some people who typically think of otters as smooth.
Athletic but not super built, a person can be an otter regardless of age and they are considered to be part of the larger bear community. Think of otters being somewhere between cubs and bears. They’re not as massive as bears and are certainly smaller than cubs.**
Such as: Scott Caan
BEAR IS…....................
**The Bear is the polar opposite of the Twink. Bears are large and in charge, wouldn’t dream of shaving ANY of their body hair and frequently don’t wear deodorant. Large and jovial, these beasts range from muscle-daddy to Sumo wrestler, are generally a little older and are usually some of the nicest guys you’ll ever meet.
Characteristically, a bear is a large, possibly heavy gay man that could also be muscular. A fairly large protruding belly is a defining characteristic of a bear.
Masculinity is also a key feature of bears, and some bears are so caught up in projecting a masculine image that they shun other would-be bears who appear to be too effeminate. That said, many bears consider themselves to be harmless and even playful.
There are several subtypes of bear, which include:
Muscle Bears: Bears whose size comes from muscle and not from fat
Polar Bears: Older bears with gray or white facial and body hair
Sugar Bears: Effeminate bears that are shunned by more masculine bears**Such as: John Travolta, James Gandolfini or even Robin Williams was
See pics attached between Scott Caan & John Travolta
WOLVES ARE…....................
**Semi-hairy, muscular, lean, attractive, and sexually aggressive, wolves are sometimes considered as part of the larger bear community or on the bear spectrum. They can be any age and normally have facial hair.
In the gay world, a wolf is a lean, muscular, sexually aggressive and semi-hairy man of any age or height. Some might also describe wolves as slimmer bears but there is a lot of disagreement on this. Most wolves have facial hair. Subgroups of wolves can be found in aging wolves, which are gay men with wolf-like features that are starting to turn a bit gray.
And then there are full-on silver or gray wolves, terms that describes an older wolf with gray or white facial and body hair.**
Such as: Joe Manganiello
Thank you so much for the clarification. 
Rustler