Playing House on the Job: This Isn't What It Looks Like (I Swear)!

Story :  Natsu Yoshizawa finds herself abruptly transferred to product development at the bedding manufacturer where she works, and then given a coveted spot on the team designing a bed aimed at newlyweds. Spearheading the project is Moriba, a man from Natsu's hiring group who's since become a powerhouse at the company, and almost as soon as she arrives he proposes to her out of the blue...!! Well, not exactly. It turns out he just wanted to "play house," temporarily pretending to be a married couple, in order to better understand their target customers' mindset. Natsu reluctantly accepts, since after all it's just research for work, but when Moriba proceeds to treat her just like an actual wife she starts wondering if she's in over her head. He even puts on a morning pillow-talk act, whispering about how adorable she was last night as if something had actually happened between them...?! Now, hold on just a second! This really isn't what it looks like...! (Not yet, anyway.)