Sensei, Mou Dame desu

When comic editor Masumi Shishio is transferred to a BL magazine, he finds himself out of his depth with this new genre, but he isn't about to let that stop him. He reaches out to an artist who's scary good at drawing the D, secures a meeting, and then finds out that the talented "Miss Akiina" is in fact a businessman named Satoru Akiba. The pair decide to make the most of being a two-man team by doing some hands-on research: photoshoots at love hotels to get the poses right, test-runs of kisses and dates to get the feelings right... even a bit of sex, just to safe!! If they want to sell a million copies, they'll have to really put their backs into it! But what if this editor-artist combo's romance simulations turn into something real...? (Source: Houbunsha)