Ijo met Chloe when he was involved with a project to conserve his power even after his death. They fell in love in the process then had a one night stand while drunk. When Chloe knew she was pregnant, she kept it a secret because she lately knew the lab keep their eyes on her (sadly the lab already knew her pregnancy and started to do an experiment secretly, without her knowing > this is the reason for Gru's coral eye color, as side effect of the experiment).
When Ijo went to conquer 99th (and 100th) floor, Chloe destroyed they lab and experiment data, released the experiment samples, runaway, gave birth, and left Gru in the orphanage. By the time Ijo gave up his power to conquer the 100th floor, he rushed to find her, but she already dead (this is why he never knew Gru is existed in the first place). If you remember the system keeps intervene with Gru (blocking something or change the rewards), it's because Chloe's soul stay inside Gru to keep her safe through system (The 'unknown title' so far actually 'Mother loves Gru so much' > Chole also put a message inside it so Gru can read it when she unlock the title.
While the master of 99th floors stay in Jurim's hand, the master of 100th floor stay in Ijo's head. Ijo went insane as the master of 100th floor tried to manipulate him to recreate the tower (his loved one already gone, everyone said bad things about his family - labelled his father as someone who sold his son to get money from conquering the tower, so what is the meaning of live? Humanity need to be test through the tower again), so he created Gnosis and disguise himself as Han Roun in the process.
Later Ijo will know about the pregnancy and search for Gru. He will appear again in front of everyone, after this and that, he will pay for his crime (as a way to make Gru proud of him), but Gru, Joorim, and his father still can visit him once in a while. He also can create a temporary body for Gru's mother, so they can stay together for a short time when she has enough power (her soul will take a rest once in a while after use her power to posses the created body
Ijo met Chloe when he was involved with a project to conserve his power even after his death. They fell in love in the process then had a one night stand while drunk. When Chloe knew she was pregnant, she kept it a secret because she lately knew the lab keep their eyes on her (sadly the lab already knew her pregnancy and started to do an experiment secretly, without her knowing > this is the reason for Gru's coral eye color, as side effect of the experiment).
When Ijo went to conquer 99th (and 100th) floor, Chloe destroyed they lab and experiment data, released the experiment samples, runaway, gave birth, and left Gru in the orphanage. By the time Ijo gave up his power to conquer the 100th floor, he rushed to find her, but she already dead (this is why he never knew Gru is existed in the first place). If you remember the system keeps intervene with Gru (blocking something or change the rewards), it's because Chloe's soul stay inside Gru to keep her safe through system (The 'unknown title' so far actually 'Mother loves Gru so much' > Chole also put a message inside it so Gru can read it when she unlock the title.
While the master of 99th floors stay in Jurim's hand, the master of 100th floor stay in Ijo's head. Ijo went insane as the master of 100th floor tried to manipulate him to recreate the tower (his loved one already gone, everyone said bad things about his family - labelled his father as someone who sold his son to get money from conquering the tower, so what is the meaning of live? Humanity need to be test through the tower again), so he created Gnosis and disguise himself as Han Roun in the process.
Later Ijo will know about the pregnancy and search for Gru. He will appear again in front of everyone, after this and that, he will pay for his crime (as a way to make Gru proud of him), but Gru, Joorim, and his father still can visit him once in a while. He also can create a temporary body for Gru's mother, so they can stay together for a short time when she has enough power (her soul will take a rest once in a while after use her power to posses the created body