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