S1 No. 1 Style or just S1 (エスワン) is a Japanese producer of adult videos (AV) which has its offices in Tokyo's Meguro Ward. The company is best known for retailing its adult videos under the Fanza brand, an affiliate of DMM.
- Country
- Japan
- Headquarters
- Tokyo
- Inception
- 2004
- Website
- http://s1s1s1.com/