That is...entirely accurate to what would happen, along with his upper jaw getting dislodged, which would warp the rest of his face.
Then...Junpei would either have a crying and hyperventilating panic attack, or he'd just go straight up BEAST MODE.

Junpei: "RRURRRRGLHHURRRRGGLL~!" *picks up Kyle and lifts him up over his head*
Kyle: DX <(Kyyaaaaahh~!)
Teacher: *sees half of Junpei's faces hanging off the other half-ish...projectile vomits*
Nozomi: "...? What's with all the yelling?"
Hakuya: *guides twin[s]cest[/s] away from scene, shrugging* "Dunno..." ... "Come here, you!" *pulls sister into janitor's closet...?*