Love my man, hate his house!

I need advice. I adore my boyfriend. We're both 28 and deeply committed. The plan is for me to move in with him when my lease is up in the fall. BUT, his place is gross. Not just messy...I'm talking never vacuumed, never scrubbed his toilet, never dusted in a year gross. I refuse to live in filth, or clean up after a grown man. How do I approach the topic without hurting his feelings?