According to the account information (of the above Nijisanji users) as of January 31, 2022
, 84% of users under the age of 29 (26% under the age of 19 and 58% between the ages of 20 and 29). 11% for 30-39 years old, 5% for 40 years old and over)
The male-female ratio is stated as 44%: 56%.
https://www.moguravr.com/nijisanji-business-plan/ 