The MC has had it rough for a long time and is facing challenges regarding social intelligence and emotional quirks. He has my respect as he is extremely driven to "loving all of his students" as a true teacher. Sure there are 3 bold and wild students who are extreme, but their actions are driven by their care and feelings. After a dozen chapters, you will discover the girls have no malicious intent, they are just thankful to the MC for being a good role model as he earned their feelings ( even if he does not know ) There is a bit of a focus on the femalebody proportions, yet it's not overpowering.
So people wondering if to read this, kindly ignore others who haven't even gotten past 10 chapters.
Zako Sensei is good, you just have to be aware of the age setting of the girls and the theme