Despite initially going to refuse, Saku ends up agreeing to help the literature club. Mihoshi acts cheerful without him there, but is still troubled by his absence. Meanwhile, the astronomy club has their hands full with making the planetarium. Mihoshi suddenly hugs Saku one day after school and rumors spread after some athletic club members see them together with Sōma. Fumie becomes concerned that Saku has been helping the literature club too much and that he may be concerned about the rumors regarding him, Mihoshi and Sōma. Hime gives Saku a journal she compiled about the planetarium's construction. Saku feels re-energized about the astronomy club and goes back to help.
文化祭をひかえ、クラスや部は出し物の準備に活気づいていた。天文部もプラネタリウムの製作をすすめていたが、文芸部を手伝うことになった朔は、だんだんと天文部から遠ざかることに・・・。