A few translated comments:

"what? Why did I just see this now? Did he seriously grab and shove her in the beginning part of the video? They must have something going on! That’s just strange."

"kkk why is this the first time I’m seeing this. The way he lead her off stage is so manly~ sehuna she’s your noona what are you doing???"

"Sehun and Taeyeon. The two members of exo and soshi who don’t give a about public perception. Daebak"

"omg…. How can he do that to her in public when she’s a sunbae? I used to think all the people saying they’re dating is silly basing it on their collaboration stage interactions but this is suspicious. You don’t do that to a sunbae and noona no matter how close… Unless there’s more to it than just that. ㅋㅋ and here I thought Taeyeon was dating someone else…"

"it’s like Taeyeon is a key to activate the human in robot Sehun. He always gets so smiley and happy when around her when he looks dead most of the time. ㅋㅋ they look cute together. Choding Taeng is cute."

"he’s so comfortable with Taeyeon. All the other members must be so jealous that he gets to push and drag her around like that ㅋㅋㅋㅋ"

"I watched this on YouTube and saw other videos too. ㅋㅋㅋ I’m not into shipping smtown members together but they sure look cute and seem to genuinely enjoy each others company. I wouldn’t mind if this was real."

*it's the highlighted blog, but b/c with naver/daum/nate blogs, you have to have a korean SSN in order to see private blogs*