The Eye of the Midnight Sun's Secret
Asta and the others safely return to the Black Bulls' base after defeating the Eye of the Midnight Sun and the Diamond Kingdom in the Witches' Forest. Now that Asta's arms have healed, the Black Bulls as well as Yuno, Klaus, and Mimosa are relieved. However, there's no telling when the Eye of the Midnight Sun or the Diamond Kingdom will try to attack the Clover Kingdom again. Klaus then brings up a proposal to Yuno and Mimosa.
Aired 15/01/2019EP 66 - The Eye of the Midnight Sun's Secret

Black Clover
In a world where magic is everything, Asta and Yuno are both found abandoned at a church on the same day. While Yuno is gifted with exceptional magical powers, Asta is the only one in this world without any. At the age of fifteen, both receive grimoires, magic books that amplify their holder’s magic. Asta’s is a rare Grimoire of Anti-Magic that negates and repels his opponent’s spells. Being opposite but good rivals, Yuno and Asta are ready for the hardest of challenges to achieve their common dream: to be the Wizard King. Giving up is never an option!
(Source: Crunchyroll)