Come in come in, we have plenty of rooms...

Eientei (永遠亭, literally House of Eternity) is the name of a large, old-fashioned Japanese mansion hidden deep within the bamboo forests of Gensokyo. It has hallways that lead out into the far reaches of the sky. Eientei is currently occupied by a large group.
Kaguya Houraisan【蓬莱山　輝夜（ほうらいさん　かぐや）】
Eirin Yagokoro【八意　永琳（やごころ　えいりん）】
Reisen Udongein Inaba【鈴仙・優曇華院・イナバ（れいせん・うどんげいん・イナバ）】
Tewi Inaba【因幡　てゐ（いなば　てゐ）】
have been hiding there since their exile from the Moon. Other occupants include rabbits—lots of them—all under the command of Tewi Inaba and Reisen Udongein Inaba, who protect Kaguya and Eirin from intruders.

Okuu in L4D
Nanoha in L4D
Reisen on drugs