Library Wars: Love & War Vol. 6 (manga)

It's Valentine's Day, and Iku's hopes are dashed when Dojo, the guy she's been crushing on—and who's her Library Force superior!—receives an elegant box of chocolates from another woman. Romantic intrigue strikes the whole team as Shibazaki meets a would-be suitor and confides in Iku about her tortured love life. And it seems that Hikaru is being followed by someone from his past...