Yamada and Kase-san. (3) The season is autumn. As always, Kase-san is busy with club activities and dorm life. On the other hand, Yamada is also occupied with studying, part-time work, and has even joined the gardening club, leading a fulfilling life. Amidst this, the gardening club decides to collaborate on creating a garden for the university festival, produced by Yamada's admired gardener, Densuke Tagame-sensei. Moreover, as a guest, the handsome actor Tomoharu Seki, known as the "Flower Bed Prince," who is currently co-starring with Densuke-sensei in a TV program, will be participating. Knowing this, Kase-san's feelings are anything but calm... Each of them experiences their autumn university festival and their first winter trip together, wanting to be together even more. What will happen to the two overflowing with these feelings!? This is the third installment of Yamada and Kase-san's sparkling youth diary!