シュク, やど, やど.る, やど.す, すく, ぶすき, やけ
inn, lodging, relay station, dwell, lodge, be pregnant, home, dwelling
JLPT3 G3 S11 F701
The relevant oracle bone form of the element now written 百 shows two figures squeezed into a bed, that shrink in curling positions. 宿 adds an element combining 人 person and 宀 roof/building → (place to) curl up and sleep → *lodging*; *shelter* → *inn*. Also, *be pregnant* (← lodge a fetus). There is no etymological connection with 百.
[Full Kanji Etymology List]