What drove me wild is the caption:

@taeyeon_ss: Happy B-day SUNNY❀ 오늘도 우리는 행복했다. 써니끼니사랑해내꺼 #515 #HPM #bd
@taeyeon_ss Happy B-day SUNNY❀ We so happy today. Sunny I love you, you’re mine. #515 #HPM #bd

"Sunny I love you, you're mine"

You have got to be kidding me, Kim Taeyeon! OMG. Why do you have to put that! My SunYeon heart is beating erratically it's driving me insane!

Then she posts this one:

She doesn't even have to write anything more. That smiley face says it all.

I can't even with this! Kim Taeyeon is driving me crazy.