It's Personnel!

Ms. Komori is the ace of the Sales and Marketing Department, and she damned well knows it. With a smile that can convince anyone to do anything, she always goes well over her monthly quota – so imagine how surprised she is after finding out she’s getting transferred over to the dull, uptight Personnel Department! But little does she know that she may have more in common with her new coworker Ms. Yamanobe than she originally thought… (Source: Manga Planet) Note: Includes one extra chapter.