Jongwoo:

He wants to mock it out of resentment as this has been him every single day nowadays, including broken sleep and nightmares.

But he knows that's not the right reaction so he will ask why you think you got it.

In the past he would have been more worried and began to playfully massage it away, or jokingly tease that he knows an activity that can loosen the body.

Moonjo:

He will show concern, which you never know if it's true or not, and offer a massage. He gives damn good massages, and accept them each time as they do solve the issue.

He knows exactly where to press, how much pressure, and what movement. Once done he'll place a kiss to the area then tells you with that handsome smile that it's done.

Junghwa:

"Oh, wae?" with worry as she thinks it might be from stress, bad sleep, etc. Or if she knows you are a stomach sleeper she'll scold you that she told you that article was right that it's the worst position to sleep in.

She'll search up ways to relieve the pain then helps you perform them as she doesn't like seeing you so tensed up.