The apartment is very spacious for 4-5 persons. There is one big room and another style Japanese. There a kitchen with a space with bed. Beds are enough for two persons each. The bathroom is little so if you need a lot of space that's inconvenient. But we were okay! We went in July so it was kind of hot in the apartment but there is climatisation in each room which is very good!
The apartment is very well located you're in a few minutes from the center of ikebukuro. The station is 5-10min walk.
Thanks!