Board Thread:Questions and Answers/@comment-44996737-20200206022806/@comment-30241447-20200206162216

I'm talking about the brotherly bond both share. Even if Sasuke was out for his blood, Itachi never stopped loving him. Even at the end when he fought his brother, he never stopped smiling. He sent him off with a, "Forgive me, Sasuke. This will be the final time." Considering what Itachi did just so that his brother can live, Sasuke is very lucky. When he and Sasuke teamed up against Kabuto, Itachi made sure that Sasuke knows that no matter what choice he makes, no matter what enemies he makes, no matter how deep into the shadows he sinks into, he will love him always.

Now, in terms of Yuu and Mika, Yuu swore vengeance on the vampires for killing his beloved family. When he found out Mika was still alive, he thanked the gods (probably) and hugged Mika, making sure he knows that even if he takes on this form, he will always love him. Mika always attempts to turn away from Yuu but he refuses to let Mika go.

Their brotherly bond is similar to Itachi and Sasuke's because it was initially forged by familial love (trapped in Sanguinem for Yuu and Mika; lived as children for Itachi and Sasuke), then melted and reforged as a bond of hate (he didn't specifically hate Mika but it is still a bond of vengeance as is Sasuke's bond with his brother after the latter committed the Uchiha Clan Downfall), and finally melted and reforged into another stronger familial bond (in both cases, their reunion following the respective parallel's deaths, Mika and Itachi).