Maga-Tsuki - Vol. 9 Ch. 41.5 - It's a secret!

[MangaDex]

 

[BakedBanana]

Couldn't you just touch feet or something? Is there a need to interlock your legs like that? (Page 9)

And I already forgot who this Michiru girl is (other than her being the MC sister?), I guess that's on me for not reading this for awhile.