A Question for Dialogue

Tackle this situation with me:

Let's say a person says they are a Christian. They go to church, AWANA, Youth Group, prayed a prayer when they were 5, serve in the nursery, read their Bible almost every day, say "Yes, Mam/ No Sir" to their parents, have all the books of the Bible memorized, go to Scholarship Camp every year, watch TBN every night, carry their Bible everywhere they go, are nice to their dog, and eat all their green vegetables.

But they sin, and are confronted.
And they don't really feel bad about the sin. It's not really a big deal to them; it doesn't seem to matter.

What would you say about that person?