After a fun day off, Chisato and Takina are back on Lycoris duty! Their latest objective is to guard and guide the elderly Mr. Matsushita on one last tour of Tokyo, but this seemingly straightforward mission might prove harder than it looks… With terrorists on the loose in the city and the mysterious Alan Institute rearing its head, can Chisato and Takina successfully finish the job?!

 

恐怖分子們展現出不安定的動向之際，
千束與瀧奈接到了依靠機器維生的老人──松下
所委託的東京觀光導遊兼護衛任務。
護衛過程中，瀧奈得知了千束也是
靠著機器──人工心臟才得以維生。

——中文簡介摘自台灣角川出版《莉可麗絲 4》