Bella Thorne Goes Topless and Touches Tongues with Tana Mongeau at 20th Birthday Party

Well, that's one way to celebrate!

If you need more evidence that Bella Thorne is not a little girl anymore, look no further than her latest antics on social media. The Disney Channel alum recently rang in the big 2-0 in the most outrageous way possible. Aside from hitting the town wearing nothing but nipple pasties, the Famous in Love star continued to fuel romance rumors with YouTuber Tana Mongeau by — what else? — packing on major PDA for all to see.

Nothing says you’re a responsible adult like a girl-on-girl romp in the public, right?

Source: Twitter @tanamongeau