Rias managed to have the boy ejaculate multiple times by playing around with only her tongue and fingers, and to her astonishment, the volume of sperms was probably more than all the semen she saw in her life combined. Yet, feeling the throbbing pulses in her hands, the towering rod had never softened for a second; instead, it looked slightly more intimidating than before. Perhaps she was just imagining things; there wasn't enough time to think as another blast of white seeds quickly gushed out.
"Boy... just what did Maria do to you??" Forming a bowl with her two hands to catch the pond of boiling thick ooze, the succubus shakenly asked.
"Erm... I ate some strange things back at the island. This is probably their side effect." The boy did not appreciate the dramatic increase in his fertility; he found it difficult getting used to the constant jammed feeling tightening in his two loaded sacks of scrotum.
At this point, it looked like she would have to take that monstrosity inside her to achieve the goal of squeezing him dry, simply teasing the stud wasn't going to be enough. How long has it been that something visited her flower? However, one thing for sure, nothing had ever remotely come close to this scale, not even her collection of toys matched him in size.
"Well, boy~~ This time, I will savor the taste with my other mouth. I hope this little Leo is as flavorful as your mother promised." She had been continuously dripping love nectars from her crotch the moment she saw the size of his massive endowment; the woman was not as relaxed as she appeared to be.
Pushing the boy back onto the sofa, the succubus raised her hips high up in the air to kiss her flower with the tip of the rod. While pressing her hands on his broad chest, she naughtily drew her head closer on top of his face. Leo could feel her hot humid breath blowing into his ears.
"Do you know why Lilith doesn't have a father anymore?" Rias softly spoke with a smirk.
"I only heard Lilith mentioned it once, please enlighten me." The boy was curious indeed.
"Because I have never experienced orgasm during sex~~ Hehe. Her late father tried his best to please me and ended up exhausting too much vitality due to his pride as a male." The succubus then lamented.
"What a shame, he was very masterful in all sorts of techniques, but I still couldn't feel it coming. Though... he was barely a third of your size, let's see how this freak of a monster will fare inside me." Feeling her flower being brutally spread... even with just the gland alone, it was already incomparable to her late husband.
Was that a challenge right there? That was something the stud could not back down from. Leo slightly relaxed the suppression of his libido and the rod began to fully erect into being. He was only semi-erected the entire time as he didn't want to scare the woman right away. Meanwhile, without looking down, the unsuspecting succubus slowly descended her hips.
"...crap, this is not good, it feels way bigger than it looks when it's inside." The woman muttered. Her eyes weren't fooling her; Leo wasn't at full force before putting it in.
However, one cannot simply underestimate a mature and ripe succubus. In retaliation, Rias clenched down on the monster inside her tunnel, the walls of her interior tightly squeezed onto the throbbing mass. Her hands also reached for the back and heavily gripped onto the two titanic orbs; she had to put extra strength into her grip due to the bloated scrotums being hardened like iron.
"How does it feel, little boy? You want to cum, don't you? Already can't hold back~~Fufu" The succubus was on a different level compared to Lilith who was still a virgin until recently.
The way he rammed his sluggish giant lump of iron was brutish and crude, there was no skill or methods behind his rough movements; all he tried to do was push that burly mass mercilessly to her stopping points. But... but! The boy's obscene size was already scraping every corner of her interior, rendering all the techniques of sex obsolete.
"Leo~~ Y-You are such a cheat! ...casually making a succubus like me crazy in lust! H-How could someone like you exist?!" Rias did not know true manliness before this hour, all the men she toyed with in the past didn't amount to a single drop of his sperm. After experiencing the revitalizing warmth of his seeds, it would be impossible for her to accept another male.
Excited in the heat of the moment, the boy broke through the final defense and accidentally intruded her womb.
"Eh!? W-Wha is this? It's in..." The succubus could feel the rod stirring the semen inside.
In reaction from the succubus, his crotch was showered with several consecutive sprays of orgasm. Rias was showing signs of fainting, which was what he tried to prevent. Leo had broken too many ladies in the past several days whenever he entered their wombs.
Leo wanted to pull back out, but not before another massive surge of torrent erupted in her sanctuary. After a long minute, when he finished dumping a hefty load, Rias grabbed the boy's arm and looked towards him with dreamy eyes and the face of ecstasy.
"D-Don't take it out... please k-keep going." There was a desire to be drowned within this pleasure, even if she had to become a fallen succubus who is a slave to the boy's cock.
Leo was impressed with the sturdiness of the succubus, as expected from a race that was born for sex. With the peace of mind that the lady skewered on his rod probably won't break anytime soon, the boy lifted up her whole body like a big toy, dialed the engine to medium and started humping away with a little bit more effort to his hips.
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When the sun finally fully rose above the horizon, Lilith let out a cute yawn and stretched her overly plump body. From her great bounties, the button of her pajama burst out, hit the wall in front and then bounced back on her head. Rubbing her forehead, the girl sniffed her nose and noticed a familiar vulgar stench heavily saturated the air.
Cranking open the door to the living room, she saw mother in her succubus form, laying submissively under the boy's crotch while servicing the owner of that enormous set of reproductive organs. While Leo sat on the couch, one of his bloated twin orbs was resting on her head, another was held in her hands and cared for by her tongue. A river of white seeds was oozing from her flower, flooding the floor and flowing almost all the way to a certain young succubus's feet.
"Ah~ Good morning, Lilith. Mommy must apologize, she has fallen from grace as a mother."
Then, Rias blissfully brushed her cheek against the heavy sphere in her hands and looked towards her daughter with the expression of a maiden in love.
"Starting from today, I will be entering the competition as a tamed succubus serving for her master. Let us work hard together, my sweet daughter."