One of the reasons this was so good was that it was simple and so natural...that it didn't feel like I was watching a BL or a love story between two male leads! Just as what Kang Seo Joon said, I really didn't want this to end.
No, Gook pushed Taejoo away before anything happened.
I think it is implied that Tae Joo kissed Gook cos the way they talked about it aftwards. You know "others will see" ... "why did you do it" ... "you always do what you want"...
Or is it just me?