Identify an animal (Japan, urban area)
I've been able to narrow it down to 3 species in Musteloidea, the weasel superfamily, but I think you observed a Tanuki that was suffering from scabies.

1) Tanuki / Japanese raccoon dog - 'Tanuki' - (Nyctereutes procyonoides viverrinus).
Visually similar to what you observed. The feet and face in particular seems to fit with a tanuki. Tanuki are often observed in urban areas in Japan and have been increasing in recent years. There are frequent reports of tanuki with scabies that have missing fur and a similar appearance:
(Google search for "tanuki" and "scabies":
https://www.google.com/search?q=%E7%96%A5%E7%99%AC%E3%82%BF%E3%83%8C%E3%82%AD

2) Common raccoon - 'Araiguma' - (Procyon lotor)
Since they were introduced in 1962 as pets, there are some wild populations in Japan, including in Kanagawa prefecture where you observed the animal.

3) Japanese badger - 'Anaguma' - (Meles anakuma)
Another possibility but I think it does not fit your observation.

There are a few other species in this superfamily but I think it is safe to exclude them due to a lack of visual similarity.