For any sales nerds that cares, here's the
shoseki sales numbers for the first volume (physical sales).
Day 1: Number 136 of 500.
Day 2: 216.
Day 3: 355.
Day 4: 367.
Day 5: 340.
Total Weekly August 26th to September 1st: 384.
Total weekly sales at 400 should be around 1450 and 300 around 1750, so it looks like it sold about 1500 books the first week.