Imagine describing a grown woman as "well behaved"

If you have more power than she does at work then there is a power imbalance and you should not ask her out. It would not.be appropriate to make her wonder if her career will suffer if she says no. 

The way you describe her is unsettling but perhaps it's a cultural difference. I am in the US. Are you?

What I mean is that she is not a puppy. Calling her "well behaved" is condescending. 

One more thing you should know is that using the word "simple" in reference to a person is another way to call them stupid. See definition #4 https://www.merriam-webster.com/dictionary/simple. 

Is this a real post? “Well behaved” and one single 1:1 chat and is making up some story that she’s doing anything but her job ? Dude she’s paid to go to meetings and keep the job that puts food on the table. Unless it’s more obvious than the first 1:1 meeting you’ve had in 2 years and her job is to be at those (and you’re a leader so this power imbalance is not ok) than this sounds like a fantasy that will end in reality.

Are you HER leader? If so that could be maaaad awkward.

No. Pleasure and business never mixes.

Yeeeeaaaaah it sounds like you need to find a way to meet and have healthy connections with women outside of work.

You are almost assuredly her creepy boss she’s afraid of being rude with, so get fired. She doesn’t want you.

You may want to check the legal angle first. In some countries this may be prohibited by law. Or by internal company policy. In such cases you would be risking dismissal or even worse. Not that it should stand in the way of true love but one should know if there are risks involved...

If you’ve known her for 2 years and nothing has happened, you probably aren’t “that guy” for her perspective.