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 BBL ending
Get Azami ending (ED no.13)
Get Yuuya ending (ED no.05)
Get Kazuaki ending (ED no.08)
Complete Torimi cafe story (ED no.12)
Get Sakuya ending (ED no.02)
Get Anghel ending (ED no.11)
Get Shuu ending (ED no.09)
Get Nageki ending (ED no.04)
Get Ryouta ending (ED no.01)
Get Sakuya full ending (ED no.03)
Get Shuu ending (ED no.10)
Get Okosan full ending (ED no.07)
Get Bad ending (the hawks party killed you)
Get Okosan ending (ED no.06)