In a quiet, sun-dappled room, a sister's curiosity leads her to explore her brother's most sensitive spots. She tentatively traces her tongue along the tender skin of his balls, her brother's cock throbbing in response. She takes her time, learning the rhythm of his breathing, the way his body tenses and relaxes. Meanwhile, he jerks off, his hand gliding up and down his length, lost in the sensation of her warm, wet mouth on him.