Here is the full list of all 16 Hatoful Boyfriend achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Get the BBL epilogue (unlocked by getting all 14 endings)
Get Okosan ending (ED no.06)
Get Shuu ending (ED no.09)
Get Shuu ending (ED no.10)
Get BBL ending
Get Azami ending (ED no.13)
Get Sakuya full ending (ED no.03)
Get Ryouta ending (ED no.01)
Get Anghel ending (ED no.11)
Get Okosan full ending (ED no.07)
Get Yuuya ending (ED no.05)
Get Bad ending (the hawks party killed you)
Complete Torimi cafe story (ED no.12)
Get Nageki ending (ED no.04)
Get Sakuya ending (ED no.02)
Get Kazuaki ending (ED no.08)