He does not pray and he lives with his girlfriend; he wants to repent and marry her

No File Exists
Check below answers in case you are looking for other related questions:
It is not permissible to marry a zaani or zaaniyah unless they have repented
Who are the women of the People of the Book whom Muslims are permitted to marry?

No File Exists
Related Answers:
Effects of marriage resulting from an illicit relationship
He wants to marry a girl with whom he had a relationship
Repenting From Adultery
It is not permissible to marry a zaani or zaaniyah unless they have repented
Who are the women of the People of the Book whom Muslims are permitted to marry?

Recommended answers for you:
Temporary and permanent tattoos – types and rulings
Are there any types of seafood that Muslims are not permitted to eat?
Why is the apostate to be executed in Islam?
What du’aa’ should a parent say for a sick child?
Dreams and dream interpretation