As Ren stood rooted on the spot, observing the burning mansion, not knowing what to do, he felt a tug on his chakra and heard the voice of Senbonzakura that said 'Ren-dono, it is a genjutsu, nothing that you see or feel is real'
Then Ren saw that the mansion was safe, but soon noticed that it was too quiet and that is skin was slightly red and thought 'This means that the illusion was so strong that my brain thought it was real and my body reacted like I was really near a big fire....Wait! The point of origin was Yakumo house...They are in danger!'
And so Ren towards the main door burst it open with a kick and rushed inside, as soon as he entered the livingroom he saw the unconscious form of Yakumo's parents, Murakumo and Uroko, but their bodies show sign of burn damage on various points, Murakumo show the most damage his arms are swollen, red, and blistered, while from the gap on his neck it seem that his back is starting to char as it slowly turning black, while Uroko seem to have only some areas that are red, swollen and starting blistering.
As he was checking on Yakumo's parents he also used his spiritual sense to search for her, and soon he found her in her room seemly asleep, but safe with no sign of burn on her, so Ren decided to concentrate on saving her parents.
The first thing he did was free them from the genjutsu they had fallen into, and then he started healing the life threatening burns on both of them, first he healed Murakumo's back where he had a beginning of a 3rd degree burn, then he healed the 2nd degree one till the point that they were only red and slightly swollen, then he did the same for Uroko.
'Can't let them think that they weren't in danger, so better leave some damage behind...' soon Ren notice the sign that they were about to wake up, so the first thing he did was to pull out from the sealing scroll a first aid kit and then he started bandaging the remaining wounds.
As soon as Ren finished bandaging them, both woke up with a start and screamed at the same time ""YAKUMO!"" and both starts looking around and soon notice Ren's figure who then say "Both of you calm down, Yakumo is safe, whoever did this to you did not attack her, but one thing I'm sure that who did this used some really scary genjutsu, luckily I had some mean against genjutsu and was able to easily free myself and come to help you just in time if not that burns would have been a lot worse, but now we have to call for help and find who did this..."
And as Ren was about to go away he heard Murakumo say "Stop Ren-kun! There is no need to call for anyone!" the Uroko with a sigh said "We know who did this, and we also know that this is an unforseen accident" then Ren ask "What do you mean?"
Then Yakumo's father ask "Ren-kun what do you know about the Kurama clan?" and Ren replies "Nothing much, only what Yakumo told me that, it is a clan that specialize in genjutsu and not many of it are left I remember well there is only your and your wife's brother, Unkai, family left of it"
Murakumo nod and then explain "Well our clan is specialized in genjutsu but some member have the rare trait of the Kurama Clan a Kekkei Genkai, every few generations, a member will be born with an incredible talent for genjutsu, that clan member's prowess in that field is so absolute that even without proper training, their genjutsu is simply overwhelming, furthermore, the genjutsu is so powerful that it causes the brain to believe anything that happens to the victim to the point where the genjutsu physically harms the victim's body in the same manner they envisioned, this fearsome ability allows the clan member to potentially kill their opponents with genjutsu."
But Murakumo stop there thinking if he should continue but Uroko take the lead and continues explaining in her husband stead "Such frightening power however is not without its drawbacks, the user is equally rarely able to control the full extent of their abilities, resulting in their subconscious regulating that power, leading to the creation of a second personality in control of that power, this personality proceeds to overtake the original, turning the individual into a monster that's a danger to everyone around them, the Ido".
At the end of the conversation Ren finally connect all the dots and says "You mean that Yakumo is same? Then how can we help her?" and Murakumo replies "We can do next to nothing, only Yakumo herself can defeat the Ido, the only thing we can do is tell her about her condition and hope she is strong enough to defeat the Ido, we also have to take Yakumo away from the village, as this was only its first manifestation so the range was quite limited, but at full power she can envelope the whole village in a genjutsu"
Then Uroko said "I'll go wake up Yakumo and prepare the necessities for the journey...." but Ren interrupt saying "Wait, I have an isolated training ground near the village but far enough to keep the others safe, we can take Yakumo there" then Uroko look at her husband, who was still thinking, and seeing that he was still uncertain he said "I can help you in case you again falls for the Ido's genjutsu, as said before it hard for me to fall for a genjutsu..." while thinking 'Thanks to Senbonzakura who will always disrupt my chakra flow when I fall for one'
Hearing that Murakumo then agree and say "Okay you will lead us to this training ground, thanks for your help Ren-kun" then Uroko asks "Will this create some problems for you?" but Ren soon replies "No it isn't a problem, I'm free from missions from the time begin, I just have to my parent that I will be away for some times, I'll go now to tell them and prepare let's meet in front of the Tatsumi Gate"
Then Ren went back home, and told his family that he won't be home for a while, and just said that he will be helping his friend with training, then he took all the necessities with him and went to the Tatsumi Gate, and started chatting with Senbonzakura while he waited for the Kurama Family 'I'm still worried about this Ido, is there really nothing we can do and just hope for the best?' and after a few second of silence Senbonzakura replied 'Well Ren-dono if you really want to help this girl there is a way to do it, but it is really dangerous and in the worst case you will become a vegetable...'