@Gyre The masked girl is the one who prompted Orsted to save Rudy's life after he nearly died (Back near the end of the Eris/Ruijerd journey). The guy is the same person that Eris met when she saved a miko from Assassins I believe.
@Grye: The masked person previously was seen with Orsted back when he murdered Rudeus that one time.
The other one is Cliff, the grandson? of the bishop?pope? and had a crush on Eris when he ran into her during the journey back from demon continent, quickly got his heart crushed when she started talking about Rudeus tho.
As for the glare at Rudy.
Cliff fell in love with Elinalise, and misunderstood Rudeus's relation with her.
While the masked girl, Nanahoshi, is a Japanese girl who got dragged along in a hero summoning.
She thought Rudeus might be similar and that's why she asked Orsted to let him live back then.
When Rudeus makes contact with her, she'll have him help her out with her attempt to summon things from Earth, and thus trying to find a way to send herself back.
Rudeus is in a whole other league compared to most people at the academy, but I've a feeling he's not really doing anything worthwhile there to develop himself further.
the girl who was with the super OP guy Orsted from a while ago, she is pretty important for filling up some plot holes.
She is the reason the mass teleportation occurred. She was summoned from another world, and unlike MC, didn't get shit for it. She has no magic capabilities at all either iirc. Her summoning caused the event.