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