It's hard to find mangas that actually use the term qpr, but I have a few that are implied/can be interpreted as one
https://www.mangago.me/read-manga/high_key_x_low_key/ poly bl, but two of the characters involved can be seen as more of a qpr. Probably the weakest rec on this list tbh
https://www.mangago.me/read-manga/i_want_to_be_the_wall/ marriage between an aroace woman & gay man
https://www.mangago.me/read-manga/kimi_no_sekai_ni_koi_wanai/ only one I have that explicitly mentions the term qpr
https://www.mangago.me/read-manga/marriage_as_friends/
https://www.mangago.me/read-manga/kemutai_hanashi/ their relationship is intentionally unlabelled, but it can definitely be seen as a qpr
ily thnx
recc stories with a queerplatonic rls