the first 17 books of この音止まれ。it’s aviable until 13.07. I highly recommend the series, and it is a great way to get enough material if you plan to read a lot this summer. (looking at you guys 
Read every day challenge - Summer 2021 
)
https://bookwalker.jp/de1422e053-5e36-4f0b-bfaf-137b04e0d22b/