My dad is transitioning
Before you read: I AM NOT TRANS. i am not pretending to be i just need advice.
hi, im felicity and a teenager. my dad is currently trying to transition (mtf) and has made a reddit for trans of 2026 and is in a lot of r/trans groups. we are completely altering our life but ive been struggling to find out what to call him. he isnt going by any feminine names or pronouns until he is in the "in between" phase (we call it the femboy phase) anyways; were trying to find out a name to call him (so we get used to it) because its always been "dad". his trans name (when he passes) is Bunni and i was thinking of Nini but i really dont know. "mom" isnt an option as my mom is alive and in my life. (me and her have issues but shes still mom and wont not be) please help if anyone else has any ideas.
EDIT: he doesnt want anything masc but also nothing to do with "mom"