WaterBearer

It's a very cliche theme of office life enemies-to-lovers/opposites attract, but is a very nice slow burn. 

Seo Hyunsoo (very pretty face with black hair & light hazel eyes) is the MC since we see things from his perspective most of the time.  He is a bit of a high maintenance guy who doesn't like unruly behavior or loud obnoxious noises, he keeps to a pretty consistent schedule, has a good work ethic and tends to not care about other people's business.  He has been transferred to a new department of a men's fashion magazine as a team manager/lead.  There he meets Baek Youngchan (blonde/light haired blue/green eyed zaddy with a babyface) who is another, rather famous, team leader in the same department.  Youngchan is kind of like an overexcited great dane, he always has a lot of energy and is generally pretty boisterous, but he is also a good worker for the magazine.  They initially meet at an office dinner where Hyunsoo hears Youngchan doing something naughty in a bathroom stall, which makes Hyunsoo consider Youngchan as a degenerate from that point on.  They butt heads in the office since they are polar opposites and seem to be able to work each other up.  There is a mystery concerning Hyunsoo's past in another department of the magazine where some troubles happened between him and his previous coworkers that serves as an interesting underlying narrative for the whole story that seems to finally start to come to a head when Hyunsoo & Youngchan's department goes on a company retreat with Hyunsoo's old department.  Something happens during this retreat that finally boils over the sexual tension that has been building for 24 chapters and it's very worth it (smut does not happen often, but when it does it is explicit and very well done imo).  There is a pretty good cast of side characters that each have their own distinct personalities and circumstances and they serve to really flesh out the story nicely and provide some breathing room for the MCs so that they're not always solely concerned with each other.  The artstyle can sometimes seem a bit simplified in the noses of the faces, but it has really grown on me and I especially like how the artist does serious or aroused faces now.  Would definitely give this a read if you prefer slow build story driven smut rather than just people having sex right away.

Edit: on Ch. 49 now and still really like this.