1x38 - Shugo Chara!

Yukari tells Kairi to obtain the Humpty Lock from Amu. During a meeting, Kairi stares at Amu and the other Guardians believe he is in love with her. The next day, the Guardian Characters hold a secret meeting and El brings the lock with her. When Il and Yoru show up, a fight erupts. Amu and Kairi find the Guardian Characters and Kairi obtains the lock. Tsukumo, who works under Yukari, steals the lock from Kairi and runs off. Ikuto appears, praises Kairi for his "good job", and goes after Tsukumo. Amu attempts to Character Transform, but cannot without the lock. Ikuto, as Black Lynx, catches up with Tsukumo and stops him. When Amu catches up, the Humpty Lock and the Dumpty Key react. Ikuto tries to open the lock with the key, but Amu becomes scared and the lock rejects the key. Ikuto returns the lock to Amu and leaves.