The reason why he didn’t show interest in any one person is bc Ryusui is literally in love with EVERYONE
Fr, I think what them have is what subordinate and employer kinda thing. Like ok, you can be buddy buddy at times inputs if needed but with clear boundaries you know what I mean? It just so happen that she is the 1st villager Senku knew thats why the trust is more rooted, but so is with Tsukasa even Hyoga later on.
Sides I think there is really no benefit in pushing them hetero pairs when TaiZuriha, ChromeRuri or MinamiTsukasa or HyogaHimura is already established even StanXeno is more stronger in my eyes
am i the only one that's kinda glad that they didn't push kohaku and senku too much? idk, they have a connection but for me, it's not romantic? like, they trust each other but in a tsukasa type of way?
also, bc of this, i thought senku was asexual but honestly, i think ryusui is the one who's asexual my man literally didn't have any romantic interest the whole time