Anyhow, I'll just go on with the summary and let you guys decide what to think of it.
Momo is sent to a branch office as punishment for her last incident, but she's optimistic about it. After all, it's a place to start afresh and she wouldn't have to see her ex-fiance anymore. Her coworkers are friendly, and she meets a woman named Sakura Honda.
She comes home to see Aoba eating one of her last popsicles and gets into an argument over it. Angry, she decides to use the bathroom first and slams over the door, only to walk in on Sougo when he's changing.
Over dinner, Sougo asks how the new workplace is like. Momo responds that every is very friendly and that she's glad that there are no rumors floating around her leave from corporate.
Sougo: I'm not asking about that. I'm asking whether there are any good men.
Aoba and Momo are dumbfounded by his directness.
Momo: ...why are we talking about that...? I'm not working just to fetch a rich husband.
Sougo: Do you think you would have any other chances to meet men outside of work?
Momo: N-not really...
Sougo: Then isn't this a good chance now? Take advantage of it and find a proper man to date.
Aoba: Hey hey, what are you saying. You shouldn't coerce her into something. Momo's free to do as she wishes.
Momo: Yes! He's right.
Aoba: Plus, you're too naive Sougo.
Sougo: What do you mean?
Aoba: I'm referring to the fact that you don't know how low quality of a woman Momo is. If she was the type who knew how to pretty herself up, she would have been married off already.
Momo (shocked): Huh?! Hey, shut up!
Sougo: I agree. You're right, but that's all the more reason we can't let her out of sight. She doesn't know how to protect herself, and her abilities as a woman is limited. If we don't make her understand right now, who knows what will happen in the future!
Aoba: And that's exactly why she needs to take it slowly! Or else she would be taken advantage of again and swallowed up like a little fish. Plus, as her brothers...
Momo: Hey! You two stop it already!
Angry, Momo stomps off to find her pudding, which is when she notices Gin walking in munching on her last treat. Exasperated, Momo cries and runs away, declaring that she needs to lock the fridge. Momo feels pressured to look for a man, and the next day she analyzes all the guys in her company. She doesn't think she can suddenly turn into the aggressive man-hunting type, but she also doesn't want the last person who she dated and had sex with to be that trashy fiance. As she sips on her juice box, she thinks how fit Sougo looked naked...and immediately puts a stop to her thoughts, attributing it to her unsatisfied lust.
Later on, she talks to Sakura about their upcoming Christmas plans, and Momo despairs because she doesn't have any. (Again, Christmas is like a second Valentine's day in Japan where people spend it with their lovers...so this is why Momo is so depressed about not having a date that night.)
At home, she asks whether Sougo had any plans for Christmas, and he responds vaguely that he does, that Aoba and Gin also had some plans too, and why she's asking. Momo gets even more depressed, since she thinks that they must all have girlfriends. Sougo hits the bullseye when he points out that Momo probably has no plans for that day. To prove herself, Momo says she would definitely be able to make plans for Christmas. Later that night, she has a nightmare in which all three of her brothers bring home their girlfriends to introduce to Momo, making an official declaration that they're getting married and thus abandoning Momo.
She does manage to find a guy to accompany her on Christmas though, except she discovers him to be a bad drunk. They near a love hotel, and Momo's dreading it since all she wants to do is to dump him off somewhere. He's leaning against her for support, on the verge of throwing up, when Sougo bumps into her.
Sougo: What are you doing here?
Momo: Uhh..uh..that is...
Drunk guy: Komatsu-san, let's hurry and make the (hotel) reservation.
Seeing as he's interrupting, Sougo turns to leave when Momo calls him back.
Sougo: That's the new boyfriend, right? What are you hesitating for? Stop hesitating.
Drunk guy: Do you know you're annoying? Did you come here to pick a fight?
Sougo: No, nothing of the kind. Tsukahara-san, please stop arguing.
Drunk guy (pushes Sougo): Then go shove off.
The bag Sougo was carrying drops to the floor.
Drunk guy: Let's hurry, Komatsu-san.
Momo: Tsukahara-san, I didn't have any intention to take things further.
Drunk guy: Why, did you want to string me along? We're here already. I know why you were chased out of corporate. I heard that you were messing around with relationships and that it even led to violence. Didn't you just want to find a person indiscriminately to comfort yourself? You're lonely, right? Isn't that why you agreed so readily when I asked you out?
Momo's shocked at his words and at how he views her. And she only has herself to blame for acting so rashly. This is when Sougo pulls her towards him and calls Momo his girlfriend, trying to save her pride. He tells Tsukahara that they had agreed to meet in the hotel area, and that she isn't the type of unchaste woman he thinks she is. He tells Tsukahara to take back his words, because Momo is the type to devote herself entirely to one man once she falls in love, no matter how much trouble it will cause her in the future. Momo stays silent, shocked at first that Sougo called her his girlfriend and ashamed and embarrassed next when Sougo continues on. Tsukahara says he doesn't believe Sougo, which is when Sougo pulls Momo for a kiss (ok, it reveals itself to not be one later on, only as a matter of positioning, but Tsukahara doesn't know that).
Momo is super shocked of course and she spaces out while Sougo dares Tsukahara to keep on watching if he doesn't believe Sougo. The guy runs off, and Momo drops to the ground. She thanks Sougo for saving her again, but Sougo says it was his fault too because he had rushed Momo to go find herself a man. He leans over his bag, lamenting that the contents are crushed and cursing Tsukahara for it.
Sougo: ...I didn't want to blame you, but can't you change even a little? You can't even protect yourself! That was the second time you had picked out trash! What's with your taste in men!
Sougo: And it's all because of your bad taste that the present is ruined now. You need to straighten up! If you could have picked seriously...then I wouldn't have to do such...such things to my little sister...
The next panel shows that they were only borrowing positions to trick Tsukahara, but nevertheless, they were really close. Momo's heart is racing and she feels guilty about it. It was the first time she has seen that kind of expression on Sougo...the kind reserved for lovers. And she feels all the more lonely. Sougo stretches out his hand to Momo, but she doesn't take it immediately.
Momo: Ah, let me pay for that present. It was for your girlfriend, right?
Momo: You're going off to the date next, right?
Sougo: What are you talking about? You've misunderstood. I was late tonight because I had work.
Momo: Then...what about the present?
Sougo: This? This is...
At home, it's revealed that all brothers bought a set of pudding (the nice expensive ones) for Momo. Gin reveals that he had sneaked away in the middle of a Christmas party, and Aoba has just gotten off his part time job. They had all made a bet to see which present would Momo like the best, and that the loser would have to treat everyone else to an expensive meal. Momo's lost for words, since she thought she would be spending Christmas all by herself, but her brothers promise to never abandon her. That is...until she finds a good man.
Sougo (pats Momo on her head): Ensuring your happiness is part of my duty.
Here Gin looks at Sougo suspiciously, and Aoba is a little confused.
Aoba: Duty? I wonder why Sougo nii-chan would think in such a way.
Gin: Beats me, I wonder why.
The chapter ends with Momo's internal dialogue, calling out to the younger Sougo not to ever abandon her again.