On the newest episode of "We Got Married" Taemin gives Naeun a gift (Candles, Bracelet, and to have EXO cook meat for her) After watching a live performance Taemin notices that Naeun is wearing the bracelet he gave her; making him freak out as you can see in the GIF set above.

(I do not own these GIFS - source http://keyeomi.tumblr.com/post/57878440020/jongtaemin-celebrating-when-they-saw-that-naeun)