夏休みのある日 (Pixiv Fanbox)

夏休みのある日、昆虫採集に訪れた森で少年が遭遇した「何か」。

「それ」は最初、木の上の方にしがみついていたが、少年の気配を感じると彼の目の高さ辺りまで下りてきて、背中のこぶ状の突起を徐々に変化させ、やがて巨大な乳房と女性器に似たものが少年の前に現れた。

One day during summer vacation, a young boy encountered "something" in the forest where he went to collect insects.

At first it clung to the top of a tree, but when it sensed the boy's presence, it descended to about his eye level, gradually changing the hump-shaped protrusions on its back, and eventually something resembling huge breasts and female genitalia appeared before the boy.