deku father could be allmight1. all might was born quirkless and deku couldve gotten that from him.
2. the reason all might chose deku is because that is his son remember only theories but still.
3. all might seems to be overly protective and worry about deku most than his other students
4. his mother didnt tell him to keep deku safe since all might family could be targeted
5. all might says that him and deku are so much alike ....because thats his kid
6.all might could have used his smaller form to get deku mom to fall for him and than tell her the truth when dek was a baby
think about it and comment what you think