The missionary_position is often mistagged as any from_front_position where the receiving partner is lying down and facing up.

To qualify as missionary_position the post must have:

1. Two characters having sex with the receiving partner lying on their back and the giving partner lying flat above them
2. They must be close to being face-to-face
3. The top cannot be kneeling, crouching, or standing. They must be more or less flat along with the bottom.
4. The duo must be on the same level, having the bottom be on a platform (like a bed) and having the top not be on the bed would count as platform_missionary_position (if they're both flat against each other) or table_lotus_position (if the top is standing straight and the bottom is lying on their back)