The Spellbook Library 4 (manga)

Under the tutelage of Ruslan, the former captain of the Spellbook Library's specialized sealing unit, Tohru and Yan begin honing their skills in sealing spellbeasts-with the ultimate goal of rescuing Shiro's full form from the confines of the Spellbook Library's shelves. But how are two library newbies supposed to compete against the Library's entire sealing unit...?! Then, when a mysterious, powerful spellbeast the likes of which no one has ever seen appears in the capital, the public relations department joins forces with the specialized sealing unit to investigate the matter. But Adil, the captain of the specialized sealing unit, seems to have his own agenda...