As other people have already written the main good point of this Manga is the protagonist Minato. She is completely aware of what she is doing and that she is walking on thin ice. She knows in which situations there is a high risk of discovery (but usually decides to go along with them for her brother). Her motivations, actions and feelings are also consistent.
In short: I never had a typical facepalm situation in which I was angry about some stupid actions of Minato, in most situations I think I would have been more stupid myself.
(Things which are NOT a thing in this manga: wearing the same jewelry/clothes for both identities, messing up while handling two phones, using some information she shouldn't have ...).
In addition, Minato's appearance and nature are also very likable. It's just easy to root for her.
On the other hand, it took me some more time to like Tooru, who, in the beginning, just looks like a silent womanizing A-hole. But this definitely changes afters getting additional information about the siblings' backstory.
At last, I'd like to mention that it seems that the Manga is about to end soon (if the Mangaka doesn't decide to introduce some new arc with additional problems), so it may be a good time to start reading this.
