My body is a kick ass machine!

Machines are the wrong comparison in one important respect: no machine repairs itself. Yours ran about a hundred thousand heartbeats today, replaced skin you didn't know you'd lost, and rebuilt part of the lining of your gut while you were arguing with somebody on the internet.

No engineer supervised any of it. No maintenance window was requested.

What's worth keeping from the machine idea is the emphasis, a thing valued for the work it does rather than how it looks parked. Then add the part machines never get: yours is on your side, running continuously, and it has asked you for almost nothing except sleep and something to eat.