Ok, I am seeing this on every forum dealing with this series, how everyone is so mad at the aunt for allowing Riki to continue working there after what he did to Shuri and maybe my reading comprehension is bad, but from what I gathered, Shuri's aunt doesn't actually know what really happened between her and Riki. I just re-read chapter 1 and after Shuri sees Riki working there and she freaks out, demanding her aunt to fire him, the aunt says:
A: " Ah, this is troublesome, he's the reason my niece hates men...."
S:"I'm the one who's in trouble! That asshole...Do you know what he made me go through?! Or how much he made me cry?!"
A; "[b]No, I don't. You[/b], never told me. Just how bad was it?"
S: "I...I don't even want to think about it. He was so cold and only thought about himself! He's just plain dirt!!"
A: "Why did you go out with him in the first place?"
S: "I was attracted to him at first."
A: See? You 2 had some good times. Besides Shuri, if he's the reason why you hate men, think of this as an opportunity to overcome that..."
S: "I don't need to overcome it!! If you're not going to make him quit, then I'll quit!"
R: "I don't mind quitting. When I found out that Shuri was your niece, I thought it would be kinda risky too. It's a pleasure to receive such an offer"
S: "It's a pleasure to receive such an offer What the....I'm amazed. I guess this means that he;s finally matured a little....Am I the only one who's holding on to the past and not growing up?"
A: "Ah, I'm at a lost! What should I do? Listen Shuri, I will do my best....to have you 2 work separately, and I'll support you, so...please? "
Shuri: "In that case...that's fine...I understand."
A: "She said it's ok!'
R: "...no, but..."
In all that exchange, it doesn't seem to me like the aunt knows it involved coerced sex. Shuri said he was cold, and uncaring, and that she really didn't want to talk about it. And ok, so that aunt was hesitant to let Riki go, since he's good at what he does, and it's her business who benefits from his abilities, but what does she really have to go by?
Her niece hates men because of Riki, but even before Riki coming into the picture, Shuri had emotional problems due to her abilities, her parents and friends were afraid of her abilities, so anything Riki could have done to her whatever minor would have shattered her already fragile stability. So her aunt can think of a million reasons of what went wrong, including possible rape, but if Shuri doesn't confirm anything to her, all she has to go by is the fact that her niece was already half-broken and Riki just finished breaking her.
Coming from someone who has sexual abuse in my background, I can say that living in the past is not healthy, so her aunt, and Minori telling her to move on is not a bad advice. It's actually the best advice they can give her, and her being able to talk to Riki is also good for her. I'm not saying that she should fall in love with him again, or that they should end up together, but if she can get over her trauma and is able to move on, and that involves being able to face Riki, then she's succeeded as a character.
So I think the trauma is being handled pretty well, besides everyone reacts to sexual abuse differently, both the victims and the people surrounding the victims.