Good Diner Inn Copain in Tokyo

Stayed in the inn, above a cafe-by-day, bar-by-night. The bartender speaks a multitude of languages, so I enjoyed three-way conversations through her to the other patrons in the bar. All-in-all, a cozy little place to stay with 3 floors (women-only, men-only, and mixed). The only con is that each floor (~20 beds) only has one toilet and one shower, so if you visit during a busy period, you need to be flexible with your usage of those facilities. I usually like to pop down to the bar for a quick drink as I wait for the shower in the evenings.

It's a bit hard to find. Remember to remember your email password. The male staff speaks Chinese. There's no elevator, so it's not convenient for people with luggage. There's a common area on the second floor. It's a little far from Ikebukuro Station, about a 15-minute walk. There's a convenience store nearby. The beds are a bit narrow.

It was okay because it was spring, but I think the room would be really hot in summer.
It's right next to the road, so there's a lot of noise from traffic, but there's Shibuyani and Shinjuku nearby, so it might be quiet if you fall asleep from exhaustion after playing around.
Avoid if you have sensitive eyes at night. Avoid if your body has a lot of heat.
Other than that it's okay

Feels cheap

Clean, neat environment.
Pretty convenient spot that is located closed to all the anime stores in ikebukuro (around 7 min walk).

Only thing to complain is how loud the staff talk over phone through out the night in the shared space area, they should consider that other people is also on call and should lower their volume when others are around.

Note that there's only one toilet and one shower for each female area and mix gender area. It worked fine for me but there might be times you can't shower/go to toilet if someone else is using it.

If you choose self-service check-in, you will receive the door lock code and check-in process 1 to 2 days before check-in. If you do not receive it, please remember to contact us as soon as possible.
Basically, 11:00-15:00 is the cleaning time in the museum. First change your shoes at the entrance to the second floor and then go to your bed. There will be a form to fill in on the bed. There is also a small note with the door locks and wifi passwords for all floors, which you can take with you.
The shower room and hair dryer are available from 7:00 to 24:00. Only shampoo and shower gel, hair dryer, and disposable paper slippers are provided, but no towel rental is provided. Therefore, you need to bring your own towels, toothbrushing supplies, and facial washing supplies.
If you really don’t have it with you, you can buy it from LAWSON or Daiso.
The saloon on the second floor is the only place where you can eat and drink, and both the refrigerator and the kitchen can be used.
The day of check-in was a Saturday, so many girls left the next day. There were many people packing their luggage and dressing up on Saturday night and Sunday morning, so it was quite noisy.
After these guests left, it seemed that there were only four residents left on the floor (one of whom should be a hotel helper). It was very quiet at night and in the morning for two consecutive days.
It's a little way from the station, but if you're familiar with Ikebukuro's otaku stores, like Animate and Otome Street, or even if you're a road junkie like me, you'll probably be familiar with them after just two visits.
There is LAWSON nearby which is very convenient.
If there is a chance next time, I would like to stay here again.

Very satisfied