Heidi Klum and Tom Kaulitz were all about the sunshine -- and each other -- in St. Barts, living their best island life.

Tom couldn't resist laying his hands, and the rest of himself, all over his wife as she rocked a tiny bikini, showcasing that timeless supermodel figure.

The couple was living it up, splashing in the water and sneaking in kisses, all while soaking up the vibe.

Heidi was totally in her element with her handsome boytoy hubby -- and she's got a thing for beach getaways, so it's no surprise she kicked off January in celeb-favorite St. Barts.

What else can you expect from Heidi? Sun, fun, and a whole lot of Tom!