Despite being a massive concrete city, Tokyo has plenty of natural thermal springs.
Among the best is Toshimaen Garden Spa. It has a tranquil setting inside a garden designed by Kenzo Kosugi.
If you want to get even more back to nature, there's Seta Onsen Sanga-no-Yu, where you can contemplate views of Mount Fuji while soaking in the buff.
Toshimaen Garden Spa, 3-25-1 Koyama, Nerima,Tokyo; +81 03 3990 4126
Seta Onsen Sanga-no-Yu, 4-15-30 Seta, Setagaya,Tokyo; +81 03 3707 8228
At Trisara on Phuket's northwest shore, all 39 villas are well endowed for maximum pleasure.
All-glass French doors open onto a 32-foot-long cerulean plunge pool that appears to drip into the Andaman Sea.
No swimsuits are required, thanks to a profusion of jungle foliage expertly tended by Thai gardeners who turn each of these outdoor playpens into secret sanctuaries.
Piles of plush towels are scattered about the area.
Between diving in and winding down, you can feed your companion from the villa's trays of aphrodisiac chocolate truffles and Thai mangoes.
Trisara, 60/1 Moo 6, Srisoonthorn Road, Cherngtalay, Thalang, Phuket; +66 76 310100; $600-1,230 per night