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