Nene Onemine is an extremely kind and mature Senpai at the school, who cares about her Kouhais and looks out for them, helping them whenever she can. She also may be very perceptive as well. This is shown in a scene when they're all in the classroom; Onemine wants Tadano to help her with something, but she seems to notice how awkward he and Komi is around each other, so she decides to leave them alone instead. She's the Senpai of the main characters, and often acts as the big sister figure, giving them advice and helping them out whenever and however she can if it's in her power to do so.

If you could sound similar to her English VA, Casey Mongillo, that would be great, but it is not required!

English VA Example: https://youtu.be/Hg6FQU9YkMs -spread throughout this clip