Did you...y'know...read the MC's thoughts? Before the long and hard night happens, he contemplates the fact that him and Tai are hitting it off super quickly, and on Day 8, Tai also says that things were moving way too fast; he just didn't explain why. Although I can see the confusion in having it happens too fast, but again, if we want a thorough explanation from the characters, guess we're gonna hafta wait on that one.