ISTG this shit has gotta be one of the most frustrating read ever (100% because of the MC). This arc is ok at best and only because it ends relatively quickly. It goes down hill from here.
Mc's (not fmc's) childhood friend arc...
About 20+ chapters on this for literally 0 progress on the relationship.
This arc then ties into...
Sex arc... another 20+ or so chapters... this arc is the last arc and it ends with them having sex in the last chapter (85).
just...
Honestly, I'd rather the manga be about fmc's childhood friend + the blonde friend and this boss lady also gets her own partner but they barely show the progress for them.
Sumi is best girl and tried hard to progress the relationship but the MC is turbo retarded.