Originally, wet hug referred to a hug that is literally wet due to tears streaming down one's face. This came about when a hug was offered to a crying person. Later on, it is often used to offer consolation to a person or a group of people in distress, especially over instant messaging apps. When used with this meaning in instant messages, wet hug is often marked between a pair of asterisks to emphasise that it refers to a virtual action, as well as to distinguish it from the other meanings of wet hug in order to avoid awkwardness.

to sport a boner, fly the sail at full mass, rock hard, etc.

when a girl rubs her vigina on you after it has already been wet via a water souce.

a mixing of water and bodily vagina juices

another form of penis hug, relating to the the other penis hugs such as booty/pussy hug and boob hug; more specifically a boob hug, but the girl proceeds to kiss/lick/suck on the end of the penis, in some cases causing it to ejaculate on him/her.