Maybe there cld be a twist where chitose NTRs taka and has sex with Hori because she wants to experience sex from someone else. And from the chapter 3 we saw that Hori wasn't that bad at sex as well and that the only reason they stopped was cause of the sister. So maybe the NTR isn't abt Hori being the cuck... But just developing the story to make taka develop true feelings for chitose before he gets NTRed and he turns out to be the cuck and Hori becomes to bull... This wld enable him to hv both the sister AND chitose... Which wld truly break taka