The parasitism of plants on the human body often appears in fiction, however until now it was limited to the expression in media such as novels, illustrations, and movies. Therefore, we created "Brain Tree" which enables appreciators to experience the sensation of plant parasitizing on their head. In this work, we used a head massager to present the sensation of plant roots invade the head. Furthermore, various tactile expressions are incorporated to enrich the experience such as the feeling that water penetrates into the head by watering, the feeling that the parasitic plant absorbs the nutrients in the appreciator’s head, and the feeling of the plant swaying in the wind. In this paper, we report the system design, implementation, experience design, and appreciators’ feedbacks in exhibitions.