コウ, さいわ.い, さち, しあわ.せ, こ, さき, さし, さっ, とも, ひろ, みゆき, ゆ, ゆき, よし
happiness, blessing, fortune
JLPT3 G3 S8 F786
A depiction of handcuffs for confining the movement of prisoners. *Good fortune* and *happiness* are extended meanings (← a prisoner's good fortune to escape his handcuffs).
[Full Kanji Etymology List]