Seriously, this dude looks like he's mid-pleasure in his mugshot:

Tulsa County Jail

Police in Tulsa, Okla., arrested an elderly perv after numerous reports were phoned in describing an older man exposing and/or pleasuring himself in the middle of a public park.

In their news release, the cops called him a, quote, "chronic masturbator."  And now his mugshot is going viral because his facial expression makes it look like he's pleasuring himself WHILE the photo is being taken.

At least this guy, 78-year-old Stephen Olsen, stays on brand.

Based on homey's history ... who knows? Maybe he was?

Olsen was booked into jail on two counts of indecent exposure.