Have you been to Nakano(中野)?
This is very famous as a town of Japanese subculture.
Nakano is located 3km north west of Shinjuku.
You can get to Nakano from Hatagaya by train via Shinjuku,or by Keio bus directly.
It takes only 15min from Hatagaya.
Nakano Broadway is well known as an otaku building (several floors of manga, anime, idol,music, toy shops).
There are plenty of Izakaya,Japanese pubs and restaurants,and famous ramen restauramts.
You do not have to be afraid of a scam or an overcharge here compared to a famous nightlife district Kabukicho in Shinjuku.
I recommend you Nakano if you visit Tokyo next time.
A single bus ticket from Hatagaya to Nakano is 200yen.
Full of local pubs,Izakaya,ramen restaurants in alleys.
Nakano main street.
An old house reminds me Showa era.