今年の年末年始は義妹と2人きり義妹とはいえ、もう何年も一緒に暮らしている。2人の時は大事な試験が控えた義妹の勉強を手伝えって言われけど…俺は…その…いや…なんというか…まぁ…こんなこといったら…兄として…その…威厳が無くなるというか…いや、なのかすっごく可愛いし…そのうち…彼氏とか連れてきたり…まぁ…そのときは立派なお兄ちゃんとして…迎える…うん…そのはずなんだけど…でも…やっぱり…男としての本能というか…俺の友達ものかのこと気になってるらしい…てか…俺をなのかと2人にしないでほしい…もうむりだってぇ…なのかごめんオレお兄ちゃんじゃなくて男だわ太ももの間から見えるパンティィぃィぃィぃィぃぃぃぃぃ！！！！！興奮した義兄の突然のパンチラ暴走。初心ななのかは戸惑いを隠せない。優しかったはずのお兄ちゃんがどうしちゃったの…スカートの奥底から顔をのぞかせる無自覚パンチラ少し背伸びするとしたからプリっと見えるパンチラゲーム中大胆に開いた股下から現れてくるパンチラ眠る美少女のほのかに空いた隙間から見るパンチラ座って開けたスカートの下に色づき見えるパンチラどの角度からも見ちゃうなのかちゃんのパンチラパンツから始まる純真なのかと困ったお兄ちゃんの戸惑いドキドキ性交全てはパンチラが悪い…そのはず。

This New Year's holiday, it's just me and my sister-in-law. Even though she's my sister-in-law, we've been living together for many years now. When it's just the two of us, she asks me to help her study for an important exam… but I… well… no… how should I put it… well… if I say something like this… as her brother… I'll lose my… dignity… no, Nanoka is really cute… and one day… she might bring a boyfriend home… well… then I'll be a good older brother… to welcome him… yeah… that's what I should be doing… but… still… I guess it's just my male instincts… my friends seem to be interested in Nanoka too… I mean… please don't leave me alone with Nanoka… I can't take it anymore… sorry Nanoka, I'm not your older brother, I'm a man. I can see her panties between her thighs!!!! The excited brother-in-law suddenly goes on a panty-flashing rampage. Innocent Nanoka can't hide her confusion. What happened to my older brother who used to be so kind… Unconscious panty shots peeking out from deep within her skirt Panty shots that pop out when she stretches a little Panty shots that appear from between her legs when she boldly spreads them during a game Panty shots seen through the slightly open gap of a sleeping beautiful girl Panty shots that peek out from under her skirt when she sits down Panty shots that you can see from any angle It all starts with her panties, the confusion of her innocent older brother, theドキドキ (heart-pounding) sex It's all the panty shots' fault…or so it seems.