Doing an unasked-for favor for someone, and then using it to try and guilt them into doing something for you.
Sam: "So Bob shows up at my house randomly with some brown bananas and is like 'hey, you can use these to make banana bread,' and I'm like 'uh, ok, I don't really bake but thanks,' and then he invites himself in for an hour and asks to borrow $300."
Joe: "That's some prime favor sharking right there. But my mother in law is worse. She keeps buying us weird vases and knick-knacks we don't need and then calls us ungrateful if we don't spend hours on the phone with her saying thank you and talking about where we'll put them in the house. We keep asking her to stop but she won't.
The most realistic name for a dolphin. Based on the fact that dolphins are complete and utter cunts who know something that we don't but are clever enough to let us know they know something without actually telling us.
In land terms the only thing as cunty as a dolphin is Teddy Sheringham, ex-Spurs footballer.
Dolphins are the Sheringhams of the water, therefore 'Water Sheringhams'.
Look at that Bottlenosed Water Sheringham herding that unfortunate swimmer out to sea where they will be eaten by sharks.
or
How can we sink that enemy submarine? I know, let's strap a bomb to a Water Sheringham and teach it to explode when they get close enough.