My Youth Romantic Comedy Is Wrong, As I Expected, Vol. 9 (light novel) — Wataru Watari

A not so merry ChristmasChristmas is almost here, but everything Hachiman has wanted, everything he might have wished for, is gone. Ever since the student council elections, the Service Club members have been at an awkward standstill. Something is broken between them, but they gather in the clubroom with the hope that things will just go back to normal. That's when Iroha Isshiki, the new student council president, brings in a request to help her with a joint Christmas event with another school. Hachiman decides to lend a hand, but not on behalf of the Service Club -- he'll do this one on his own.