Roger looks at the young woman that is walking towards him, at first sight he thinks this is a waste of time by the woman's frail look but quickly notes to not underestimate her and to stay on guard as with any shinobi, this woman may have some tricks up her sleeve especially because he sent the request to meet a strong opponent at this terrain, he kept alert while observing the aloof woman's comment to him.
As soon as she throws the kunai, the speed of the kunai and the small ball at the end gets immediately noticed by Roger so standing his ground, he throws a wind kunai to intercept the opponents kunai and as the weapons clash, the small ball detonates to blind Roger who puts his arm over where his eyes would see the light-source and blocks that with his fore-arm to weaken the effect it would have on him. He also squints his eyes but at the same time looks forward and at keeps alert with the rest of his senses to his surroundings. He sees the woman having quickly charged at him but notices how she gets blinded too by her stopping and the instinctive defense of putting up her arm. She was much closer to the light-source then Roger was and attempted to travel past it, with her moment of confusion for getting blinded by her own light bomb. Roger takes advantage of this and quickly throws 3 wind-infused kunais with paperbomb attached to each of them with his other arm. One is aimed directly at her while the other ones to the sides of her body. The young woman wouldn't be able to see any of the kunais approaching from her own blindness, confusion and/or instinctive behavior of putting up her arms over her eyes. The kunais travel fast and all explode in close proximity of her, with one stabbing her body first. The light wears off as Roger looks at the woman on the ground, incapacitated. Her mistake being her downfall, Roger facepalms as he throws a last paperbomb tagged kunai to put her out of her misery before walking away.
Hmm, they say ignorance is bliss, but I wonder how that felt.