Putthipong Assaratanakul is a Thai actor and singer. He appeared in the film How To Make Millions Before Grandma Dies and in the series My Ambulance, I Told Sunset About You, and I Promised You the Moon. As Billkin, Assaratanakul has released songs such as รู้งี้เป็นแฟนกันตั้งนานแล้ว (Safe Zone), Golden Hour, and กลับมาคบกันเถอะ" (Please Please).