Yuuto-san's Scent...
The Nogizaka family visits Yuuto's house for a Christmas party. However, the party is cut short when Yuuto faints, having worked himself to exhaustion to buy Haruka a Christmas present. When Yūto regains consciousness, Haruka declares that she will stay by his side in order to nurse him back to health, under the guidance of a very questionable guidebook prepared by Mika. To preserve the Christmas spirit in spite of Yūto's poor health, Haruka decorates his yard with Christmas lights, and presents him with a Christmas present. He in turn presents her with his present: a ring called "Clair de lune" which, at Haruka's request, he places on her ring finger. The two thus share another precious memory together.
Aired 27/10/2009EP 4 - Yuuto-san's Scent...

Haruka Nogizaka's Secret: Purezza
Haruka's manga and anime hobby is still concealed by her dear friend Yuuto, but Yuuto's other female friend starts to feel affection and attraction towards him, so a feelings war begins among their circle of friends. Meanwhile Yuuto tries to make Haruka happy doing what she likes the most: drawing manga, watching anime, and attending special anime events.
(Source: Anime News Network)