…you ask her out and she needs to pray about it before giving you an answer.
…she never talks to you at churchly singles mingles without a less attractive, more boring, more annoying female friend around.
…she only invites you to group activities.
…she is popular at church and you are not.
…she tells you you’re a “great guy.”
…she tells you that so many girls are looking for a godly guy like you.
…she puts you on the prayer team tree and you’re not the person she’s supposed to call.
…she praises the worship leader/hot missionary/Habitat for Humanity organizer’s “servant’s heart” too much.
…the pastor instructs everyone to reach across the aisle for prayer and you get to hold her hand only to find out it’s cold and limp and she doesn’t give a quick, churchly squeeze at “amen.”
…she calls you a brother in Christ.
Haley's Halo 
I lol’d.
…she tells you she’s seeking godly counsel with the pastor about her relationships.
…when you ask her out, she makes sure to tell you she’s a “spiritual virgin” or “born again virgin” who’s “saving herself for marriage”.
Here’s a huge red flag, even if she’s interested in you: she’s a grown woman (20 or over) but tells you that she can’t marry or even court without Daddy’s permission. If she’s saying that just to get rid of you, consider yourself lucky; otherwise you have serious Daddy’s girl issues to deal with.
Those nice girls can be prreeetttyy tricky..
If you’d like a good look at what those warning flags look like, check out “Quiverfull” by Kathryn Joyce.
OT, but I love my avatar here; looks like a Christmas present.
“I lol’d.”
Same here. Sounds like a whole bunch of Boundless scenarios.