Both of them, Song Jihyo and Kang Gary;
Who has been in a relationship since 2011,
For the whole 3 years of the relationship,
Kang Gary, who keep bring along a diary with him whenever he go,
It some kind of a precious diary for him.

In the year of 2014,
24th February 2014,
Unexpected thing happend,
Song Jihyo finally had her chance to read what he wrote inside,
As she read the last words; it was written,
"I'm sorry~"