I find people easily fooled by Brett's carefree appearance. If you look closely, Brett is actually the type of person who is always calculating and caring for others. Sometimes I even find him a bit too nosy. Brett definitely has feelings for Hayden, it's just that for some reason (Pride?) he still limits himself from showing his special feelings for Hayden (even though his actions betray him)
In the beginning when Brett first approached Hayden, it was never shown implicitly, but I get the feeling that Brett watched Hayden for a while after maybe sensing his pheromones (just based on how Brett is like in the later chapters). That's the only explanation I have for how Brett may have chosen Hayden to make the proposition he made. Was that ever explained or implied anywhere?
agreeee brett is literally FLYING/rushing back after his game in another state to make it in time for hayden's rut (and didn't even eat dinner) that's not what you do if you're just horny! brett has constantly been paying attention to hayden and caring for his needs even if he himself doesn't see them as the result of any feelings
The interesting thing is that even though it seems like Hayden is the only one who thinks and worries about this relationship, the truth is that Brett puts the most effort into this relationship. Brett learns and observes a lot about Hayden, from the past, to health problems, his rut cycles, even the acting dream that Hayden seem to gave up... while Hayden only starts to care about what kind of person Brett really is until chapter 18.
Many people say Brett is so masochistic that he has to have sex with Hayden even if he gets injured. It's a bit contradictory, but I feel like Brett in this chapter is more worried than horny. Brett didn't even look like he wanted to have sex that day, but because he texted Hayden and got no response, Brett had to rush to Hayden's houseto check. I think Brett is doing the right thing in the deal, despite his condition. Speaking of being responsible to this extent... there's no way Brett isn't serious about Hayden.