No missable achievements (plus 16 unknown)
Sign in with Steam or Xbox to track your progress, and:
Complete Torimi cafe story (ED no.12)
Get Bad ending (the hawks party killed you)
Get Kazuaki ending (ED no.08)
Get Nageki ending (ED no.04)
Get Ryouta ending (ED no.01)
Get Sakuya ending (ED no.02)
Get Yuuya ending (ED no.05)
Get Sakuya full ending (ED no.03)
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 Azami ending (ED no.13)
Get Shuu ending (ED no.09)
Get BBL ending
Get the BBL epilogue (unlocked by getting all 14 endings)