The letter does not include the sender’s name — but the letter does include white panties.
The summer 2019 anime adaptation of the Kawaikereba Hentai demo Suki ni Natte Kuremasuka? light novels have its home video releases being handled by Kadokawa.
The work comes from Tomo Hanama which began back in 2017 and has seven volumes out as of its summer 2019 premiere.
The DVDs are priced at 11,000 yen each while the Blu-rays are priced at 13,000 yen each.