There's a bit of text on the fourth panel that's hard to see because it's all in white.

i dont get it.

Ikazuchi00 said:

i dont get it.

M = Masochist
S = Sadist

still don't get it??

Is this S&M or I'm just a dirty person.

Is this a combo breaker joke?

Well, since the source provided is a repost on tumblr from a twitter post by nonco a year ago... It's the 2015 Summer Comiket table details.

Interesting that Nachi is an M and not an S

the 3 upper talking about place which is M-03.
while the last panel is the joke which misleads it. And the frog TTK doing the tsukkomi to Myoukou.

MajorAmiruddin said:

Interesting that Nachi is an M and not an S

Really? I myself see her as quite the M or at least, have quite a submissive side to her due to how she speaks. But Ashigara though. Totally thought she was supposed to be an S.

This must be how Myoukou keeps order in the family. She cracks the whip =D

Djoko said:

the 3 upper talking about place which is M-03.
while the last panel is the joke which misleads it. And the frog TTK doing the tsukkomi to Myoukou.

It doesn't help that the original is ambiguous ("I am S" vs "It's S", since the sentences don't specify subject) and it gets lost in translation...

Keough said:

Is this S&M or I'm just a dirty person.

No, it's not just you. It's a depressing familiarity with Nonco's naval base.

MD5 mismatch of http://pbs.twimg.com/media/CHUV3YEVAAAOt8l.jpg:orig

Fullsize already exists at post #2673623