User blog comment:Miskos3/Fairy Tail 514: Dragon Seed, Review/@comment-25111584-20161212114038/@comment-7418318-20161212131151

I don't think simply wrapping him in blankets will cut it. That might work for a real-world Human whos body still produces heat, but with Natsu the cause is magic, so it's quite possible that his body isn't producing any heat anymore. Looking at how Lucy was dressed (when she was still dressed) without showing any sign of cold, it can't be all that cold in that room.

Pre-heated blankets or items will only keep warm so long and thus would require constantly going in and out of the CSW. And the benefit would be pretty much the same as sharing body-heat, but with more effort.

So I disagree that the body-to-body is a bad idea, but that they use only that is indeed not very sensible.

Lucy should have Virgo bring them some blankets or have Aries wrap them in her wool, but only to make sure that as much of Lucy's heat will stay inside their covers and can go to Natsu, instead of disipating away into the surroundings (and it'd also have thwarted most fan-service criers, since we might know that Lucy was naked beneath the covers, but didn't get/have to see it). I don't think just keeping what little heat Natsu's body still retains would likely not be enough, so someone would have to be under the covered with Natsu to provide the necessary heat.

That being said, I do agree that this is basically just fan-service providing... for the reason I already mentioned: If you want to do the body-to-body properly, you'd make sure the blanket coveres them as much as possible... which it clearly doesn't in those two frames. Not to mention that leaving Lucy with her underwear on would have a negligible effect on her ability to pass on heat to Natsu, if any at all.

I too am most certainly sick and tired of Mashima stripping Lucy out of her cloth at every opportunity he can get away with.