My Youth Romantic Comedy Is Wrong, As I Expected @ comic, Vol. 18 (manga)

Full steam ahead toward prom! The Soubu High School Prom is at a standstill
now that
Yukino's mother is on the scene. Seeing how much Yukino and Iroha
want to hold the
event, Hachiman plans a separate prom of his own-a
move that'll inevitably lead to
conflict with both girls, and will
require asking for help from others. Yui has a question
for Hachiman: Just
what is he thinking....?