Karsai / lingam (prostate) massage is a real niche in Phuket — there's no dedicated scene, just the odd venue that offers it (THE KISS CLUB in Phuket Town's Phoonpon Plaza lists lingam alongside soapy and B2B) and the occasional happy-ending shop where a therapist can do it.
Where it's offered, a session sits in the 2,000~3,000฿ range as a specialist add-on. It's thin enough that you choose on reviews rather than walking in cold, and confirm exactly what's included.
Mostly Phuket Town and by appointment; afternoon into the evening. The 1 venues below are live-ranked by 7-day visitor traffic and recent reviews. Updated daily.