I am from the french countriside, and this is exactly the type of boulangerie I have been looking for while in Tokyo.
I wish that they would make their pain au levain more accessible (more variety, and available in miche, demi-miche, batard, etc..) and available earlier (I stopped to buy bread for breakfast and it was not ready yet) but otherwise the taste is spot on.
The staff understood what they were talking about, and despite not being able to buy the pain au levain that I wanted (apparently buying bread for breakfast is not a thing here) they were very kind, and able to re-route me to an alternative option without trouble. What I was impressed with is that they did not reroute me to the standard Japanese go-to friand a base de pate feuilletee sucree (sweet layered dough super common here), but to a seigle alternative that was quite appropriate for proper cheese and cured meat (saucisson).
The most authentic, and all around best boulangerie in Tokyo!