Okay, am I watching a kids show or a J-dorama? Either way, I guess the same rule applied, the main character has to go through extreme hardship, and cannot simply be happy
After Mio's death, Wataru went back through time (!) to prevent his father, Otoya, marrying his mother, Maya. Basically preventing his own birth. Time paradox? Doesn't matter, I guess this is the only way to see Kiva fighting Dark Kiva. Oh, Wataru is a such a weakling, beaten up by Otoya in the old IXA suit. I miss Jiro & friends, and their respective Kiva forms. They are not used much anymore ever since Emperor form is introduced.