Bikini-Clad Miley Cyrus Jet Skis With On-Again Beau Liam Hemsworth

 GSI Media

Hold on tight!

Liam Hemsworth put his arms around on-again girlfriend Miley Cyrus as the two jet skied in Orchard Lake, Michigan Sunday. Joined by pal Erin Lucas — who appeared on the first season of MTV's The City — Cyrus, 18, flaunted her sexy beach body in a ruffled beige bikini.

(Hemsworth, 21, is in town to shoot scenes for his new movie, A.W.O.L., costarring Teresa Palmer and Aimee Teegarden).

After working on their tans, the group of friends went on a fast food run. "How did we just order $80 worth of Sonic?" Lucas, 25, tweeted. "And then add more to the order?"

Cyrus and Hemsworth have kept a relatively low-profile since rekindling their romance earlier this spring. Hemsworth — who stars in next year's highly anticipated Hunger Games movie — has even earned the approval of Cyrus' older brother, Trace.

"We're homies," the former Metro Station rocker told Us Weekly in June. "I support my sister in anything she does."

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