Game from a developer Kamebeya, here is the link to dlsite:
http://www.dlsite.com/maniax/work/=/product_id/RJ137900
You can download free demo and buy the main game
The name is 脱衣ガンアクション "Strip-gun-action"
Aim of the game is shooting enemies and not losing your clothes, using different weapons, it has 27 pictures you can unlock, and it looks like on demo you can play only one lvl.
Some screenshots: