@Sero sorry, have to disagree with you. I think Toono x Kashima was en endgame from the beginning. Toono and Yacchan was important for plot as Yacchan is Kashima cousin and their relationship is also a part of each other character development. Besides Yacchan relationship with Toono and events involved made Yacchan a better person, so I assume author's idea would be for Yacchan to grow as a character by the end (idk if they'll end with Tamura). Also same fare for other characters as well.