Words › JLPT N1 › 契る

契る: to pledge

契ちぎる chigiru

to pledge; to vow; to have sexual intercourse (esp. between husband and wife); to share a bed

JLPT N1Everyday actions

二人ふたりは、来世らいせでも一緒いっしょになろうと固かたく契ちぎった。

The two firmly vowed to be together even in the next life.