After the demo Rex dismissed every one for lunch and when he was sure that he was alone he collapsed breathing hard.Someone held a glass of water and He took it and drank it.

"You don't need to put up an act in front of them you know?"(Flender)

"I do, for Tachi's sake besides I don't have much time left."(Rex)

Flender was also in Yu Xiaoguang office the night Rex explained his origins but the shitty author forgot to include any lines from Flender hence this would be plot hole would have formed.

Flender said nothing he never understood those genius types.

"What do you mean you don't have time?"(Flender)

"...*sigh* when two souls fuse there are two things that can happen one one of the souls completely devovers and erases the other or they fuse becoming one while one stays as the main the other stays as a sub.The process that 'thing' started was the former so in order to prevent Tachi's soul from disappearing I had to create a hiding place for it to reside and heal but that 'thing' also set up monitors to see which soul is in control or if 'I' am still under their control and influence and in order to hide from the monitors the hiding place also became his prison so I did the only thing I could in that situation I sacrificed most of my soul in order to heal Tachi and then switched our places but his soul was seriously shaken up with his last stunt so I had to switch our places again and now his Soul is almost fully healed I have to switch again."(Rex)

"How long until you switch and when will we see you again?"(Flender feeling that Tachi will be gone for quite a while)

"Tonight and probably when Tachi breaks through rank 65 that's when 'the self' trial will begin"(Rex)

Rex then stood up but nearly fell again and Flender caught him and Rex smiled it was nice to actually have some one who cared about you.

After Rex had rested and recovered enough they went for lunch where they saw the devils up to their usual antics but they had kept a chair vacant and reserved for their missing friend.

Rex smiled at this and joined the teachers at their table.

After lunch Rex had both the students and the teachers.And explained the uses of Yin seal and the requirements for it.

"I know that the subtle control is difficult for most of you so I have modified the seal so it will gather spirit power without you having to push it.To use it all you have to do is focus your spirit power on it and say release it can even be a whisper or its fine to even think about the word and it will activate"(Rex)

"Now where do you want it engraved and no private parts please I do not like to be put in an embarrassing spot"(Rex)

The Teachers either had it on their forearms or shoulders but a pattern arose when it came to the devils.

Tang San and Xiao Wu had theirs on the back of their necks.

Dai Mu Bai and Zhu Zhuqing had theirs on their right shoulders.

Oscar and Ning Rongrong had theirs on their the hand which did not have their spirit emblem.

Ma hong jun had it on the corner of his left eye.

"It should saturate and become active in a year or two"(Rex)

"Now for a class on battle strategies of course the teachers can stay if they want to"(Rex)

Rex spent the rest of the day teaching the devils and the teachers different battle strategies and importance of observation and deduction as well as how to use a person's behavior and patterns against them as well the importance of controlling the flow of the battle as well as things he had learnt over his career.Yu Xiaoguang joined him half way and offered advice from his own experiences.

After the lessons on battle strategies Rex dismissed them and returned to the office with Yu Xiaoguang who caught Rex who collapsed as soon as they entered the office.

"Is it time?"(Yu Xiaoguang)

Rex nodded and gave him a black box.

"If Tachi ever asks you about me or you feel Tachi is ready to learn about me, give him this and tell him about me and pay a little more attention to him he will not be able to control his emotions as much he did before."(Rex)

Yu Xiaoguang nodded and

"Our time has been short but I am glad I met you Rex.I am glad to have been your friend"(Yu Xiaoguang)

"Same, and see you in a few years"(Rex smiling and holding his hand for a hand shake which Yu Xiaoguang obliged)

Rex popped and Yu Xiaoguang hid the box.

The next morning Tachi woke up breathing hard as if he had just woken up from a nightmare and looked around Yu Xiaoguang and Tang San who were taking care of him were suprised and then went to calm him down.

After Tachi calmed down

"Where is Rex?"(Tachi)