After some reasearching, I dont understand why she needs to do it with a bunch of different men, it just says 'sexually sated'. Maybe its a cultural thing where japanese men have little desire for s**, or have really long refractory periods? 
Comment by Gemma Starstruck on Mushoku Tensei - Isekai Ittara Honki Dasu - Chapter 63: The Genius's Secret
1 Reply
Either ;
1. She's scared that one guy wouldn't be able to keep up with her curse or won't be able to help but view her in an inappropriate way only, in Cliff's case, she may be hesitant since he seems to come off as a very innocent person
2. At some point, she and her lover may be separated bc of some circumstances ( studies, jobs, etc,, ) and if her curse starts acting up during that time, she has no choice but to do it with other men, so she feels bad for what her s/o would have to go thru or afraid that her lover would leave her bc of that
Maybe..???
1. She's scared that one guy wouldn't be able to keep up with her curse or won't be able to help but view her in an inappropriate way only, in Cliff's case, she may be hesitant since he seems to come off as a very innocent person
2. At some point, she and her lover may be separated bc of some circumstances ( studies, jobs, etc,, ) and if her curse starts acting up during that time, she has no choice but to do it with other men, so she feels bad for what her s/o would have to go thru or afraid that her lover would leave her bc of that
Maybe..???