Here is the full list of all 15 Boobserman achievements.
Detonate 1000 bombs
Collect all the negative bonuses
Complete the game
Get caught in the explosion
Complete the game without blowing yourself up
Collect all the positive bonuses
Unlock Yumiko
Unlock Mizuki
Detonate 200 bombs
Unlock Aki
Detonate 100 bombs
Get caught by the censor
Unlock Shizuko
Unlock Naomi
Complete the game without getting caught by the censor