[Flying Dagger]

Its all about the skills and weapons the heroines have access to. Heroines often have less than optimal stat in the NG+ ranges: iirc my Yuela does not even have anything close to 100 str when she hits lv99 while other primary melee damage dealers (the dragon/NG+ chars... Kohakuren got 100 int really early in the lv70s).

In fact the heroine are often gimped due to the way they are designed. Yuela's high evade score is useless as most enemies in NG+ dungeons have bonus hit chance (some goes up to 145), that's when her low con becomes a liability. Serawi's primary stat is spread between both str and int thus her damage is always abysmal.

But stat does not matter as much when you have +% modifiers from skills. Prevail gives up to a 50% boost in stats which makes all the difference in the world. Of course, for any casters, getting Double Action means you double the damage you do: that is if you are doing any at all.

Other factors also help such as base resistance (important as heroines can gem for them). While doing the Yuidora mine NG+ dungeons having a +Death skill or weapon will make you an effective unit even if you do not do any real damage (Ragsmuela comes into mind: she can take on a whole room of gobles by herself. Dealing 1 damage per hit does not matter when you have +Death weapons and vorpal counter to insanely kill off your enemy).

Then comes the NG+ lv90 dungeons where +Death no longer works. Skills such as prevail, projectile defense, magic resist, soul shield becomes increasingly more valuable. Stat wise, luck becomes more apparent as a dps modifier.

I think Eushully recognize the terribleness of Suina due to stat capping and decided to give her the bowling ball to compensate. +40 str with high crit chance is almost on par with endgame weapons.

//

Side story:
Arterial of Origins also uses the same music for all the h scenes. I raised an eyebrow when I hear the music being used early game during a scene where the protagonist dreams about his family during NG+ playthrough...