About BDSM...

What would an S taking proper care of an M look like? I mean.. isn't the point of it for the S to be ruthless to the M (most of the time)?

If you look on page 20, after the uke gets slapped he looks offended but he actually starts blushing. Of course, there isn't any definite answer, and just because he blushed doesn't always make it consensual, but on my analysis, the uke is actually an M who has always thought he was an S, so when he got slapped, he was shocked but he blushed- and that was kind of like his inner M coming out.

However that was just my take on it.. I don't expect many to agree and that's fine.

This is yaoi, so I really shouldn't read too much into it. And did seem the uke did enjoy what they were doing.
For me I just don't like BDSM without safewords. I think the motto goes for BDSM: safe, sane, and consensual. At least for a lot of those who practise it. Some of the safety comes from having a safeword. A way they can get out of situation if they truly dislike what is happening. The safeword could be some random word like "lemon", this way the submissive can scream "stop" and "no" all he/she wants. The dominant knows they're enjoying it as long as the safeword is not used.

And of course the point of BDSM is for one to have more control/power than the other. This can be expressed different ways and to many degrees. Some is more about "mind play" (humiliation etc.), while some other is about pain. A lot of the time it's a mix of both.

It's important to remember that in BDSM the submissibve is not unwilling. They LIKE what is happening and they CRAVE it. Some do it 24/7 and have a permanent dominant. Others have their ordniary life where they are not submissive and in their "sub space", and they have sessions/scenes with a dominant when they feel the need.

I only have the very basic of knowledge about BDSM, but it really annoys me when someone can just "see" who is submissive, since that is not how it works. The uke here did seem to enjoy it, and I would have been really happy if it didn't seem like he believed himself an S. yeah, so maybe he isn't an S, but it isn't some random seme's job to come along and force him into seeing his "true nature". Oh, and again... safewords are important. But this is a yaoi and I'm just silly for putting my real life ideals on it. I don't really expect the mangakas to know stuff like this ^^

Seems like my wall of text reply didn't get marked as a reply to your comment ^^
I totally understand why you see it the way you do. Nothing odd about that since this is yaoi. It's more my personal hang-ups that get in the way for to truly enjoy this. Feel free to read the wall of text I wrote if you're interested in why.

Ahh, that's what you meant by "safeword". I never thought about that... I'm not exactly familiar with BDSM at all either. So yeah, I can see now why that'd be important. It'd be really hard to tell what's consensual or not otherwise. And wow, you actually made BDSM way clearer to me. Thanks for that. :)