Stanley "Stan" Pines is the deuteragonist of Gravity Falls. He is Dipper and Mabel's sly, cranky great-uncle who runs the Mystery Shack, a tourist trap full of questionable oddities and mysteries. When he's giving tours or sleeping on the couch, Dipper and Mabel are usually sneaking out to explore the town's secrets.
There are roughly one-sh*t billion tropes so PLEASE look through them before adding one. Otherwise add what you like. ADDITION: PLEASE read through the trope description provided before submitting something. It's not a huge deal but too often people submit characters that don't fit just because they misinterpreted the title...