Stay away (BAP zelo & jongup)

Choi Bona is missing and her little sister Choi Soram suddenly appears in front of her lover Himchan. Himchan suddenly questions Bona's disappearance everyday to Soram that leads to hurting her. Zelo and Jongup who are crazy in love stay guard over Soram and try to help her find her sister. Who will she end up with and where exactly is Bona?