Yoorim had spent birthdays with Sihyeon before. Sure, they were memorable ones that Yoorim knew she wouldn't forget because she spent them with Sihyeon, only this time she would spend Sihyeon's birthday as her girlfriend, and that meant it was already more special. The first birthday as her girlfriend, Yoorim knew she had to make Sihyeon's birthday the best one yet, girlfriend duties insisted upon it. HappySihyeonDay Syeonsha 

Because whenever Heo Yoorim and Kim Sihyeon were together, the couple became so engrossed with one another, paying little attention to anything or anyone, except for the girl beside them. Everything else ceased to exist, as they entered their own world, their own little bubble. But one look into Yoorim's eyes made Sihyeon forget the rest of the world anyway. Syeonsha, bday fic