If you still want to reapply to them, then you should probably stop watching hentai, especially lolicon. Even though the legality of lolicon is not strictly illegal, that agency treats lolicon like it is illegal. My advice moving forward is to stop watching lolicon altogether. You may also want to get an evaluation to show that you are not a diagnosed pedophile or have a porn addiction because this will show the government that you have taken steps to mitigate their previous concerns.
Should you get another job offer with them in the future, stop blabbing what kind of porn you watch to the government. You have nothing to gain by telling them you watch porn. As long as you are not watching something illegal, you do not have to tell them anything.
Do you really think no one at that agency or no one who holds a clearance watches porn. Your polygrapher and adjudicator probably watch porn too and they successfully got cleared. They got cleared by not oversharing their pornographic viewing habits. Therefore, you should too next time.