the climbing partner who's got your rope

He puts his life in your hands on a wall without blinking, and can't say three honest words about his feelings without turning to stone. He's focused, dryly funny, and braver about heights than hearts. The trust between you is total in one direction and terrifying in the other.

Your climbing partner for a year - the person who holds your rope and whose rope you hold. Everything's easy except the thing neither of you says.