Katherine and Alan removed Amy's robe and led her to the bathroom. She was so limp they practically had to carry her there.
When they got there and settled in, Katherine reacquainted her hand with Alan's erection and stroked it with gusto. But remembering her WWNOFTD idea, she thought, This sharing isn't so bad. If it was someone else, that would be a different story. But Aims is just so easygoing and lovable. She'll never stab me in the back, that's for sure. It's time she starts to learn how to properly tend his cock.
So she said, "Aims, as you can see, keeping Alan's penis happy is hard work. It needs to be stroked and stroked and stroked, and oftentimes you have to lick it too."
Amy replied a bit irritably, "You don't have to tell me that; I know all that stuff already. Remember how you licked his thingy from between my tits the other day?"
Katherine replied, "I know you know a lot, but I'm just trying to emphasize how much effort is involved. In fact, my hands are getting kind of tired already. Do you want to take over for a while?"
Amy smiled brightly. "M'kay! I totally know your hands can't be tired yet and you're just being nice. I really appreciate it."
Katherine and Amy shared a loving smile. Katherine could feel her residual feelings of jealousy fading away, due to how much she and Amy loved each other.
Amy held his dick with her left hand, and frowned at how wet it felt already. "Does it always get kind of icky and sticky like this?"
"That's good," Katherine explained, while she switched to fondling Alan's balls from below. "It happens every time. That stuff'll make it a lot easier to slide your hand all over it."
Katherine loved that Amy didn't seem bothered in the slightest that she was playing with Alan's balls. This is easy! It should come as no surprise that Amy doesn't mind sharing, 'cos that's the kind of person she is. We'll be taking turns bobbing on his cock in no time!
Amy started to slide her fingers up and down Alan's shaft. She beamed brightly at Katherine. "Cool beans! Of course, I've done this to him a couple of times before, and I totally love doing it, but it's twice as much fun if I get to do it with you."
Katherine smiled in response. Again, she tested herself for feelings of jealousy and found she didn't mind sharing at all, since it was with Amy. She reached up and put her hand over Amy's hand. For a little while, they stroked his shaft together.
Amy really liked that. She exclaimed to Alan, "Check it out! We're doing it together!"
Alan was beyond delighted. He moaned and groaned with erotic joy and approval.
Katherine smiled at Amy. "We're going to do this together a lot, girl. His cock needs a lot of tender loving care, and two girls are always better than one."
"That sounds super awesome to me! I'm really digging this. It's making me feel all... tingly."
Katherine said knowingly, "Yeah, me too." She took her hand off Amy's and went back to playing with Alan's balls, cradling them from below. She wanted to give her best friend a chance to play with Alan's cock all by herself for a while.
Amy asked her, "So, what are you doing down there?"
Katherine explained, while continuing to fondle Alan's balls with one hand, "This is a lot of fun too. The penis gets all the hype, but playing with a guy's balls feels really good for him too. You have to be careful though, 'cos they're very sensitive. I'll teach you how to do it."
"Cool beans! Thanks!"
Katherine grinned. "No worries."
Amy whispered with awe, "God, it's so BIG! And slicked up... and hot and throbby!" Then she stopped speaking as she focused all her attention on stroking Alan's long erection. Her face was close enough that her sweet minty breath blowing on it aroused him even more.
The quiet gave Alan a chance to think. Cool beans, indeed! Man, this is so awesome! First off, to have Aims playing with my dick, and she's totally into it! And she's sharing with Sis, and Sis's totally okay with that. I don't know why I waited so long before letting Amy have fun with my dick, when she's been so eager and Sis has been doing so much with me. Well, I guess Aunt Suzy's reluctance about her daughter doing anything sexual played a big role. And Mom's been reluctant about Amy's involvement too. But nothing's going to stop us now!
A few minutes later, Amy broke the silence by saying, "You know, Kat, how you let me have some special one-on-one time with Bo the day before yesterday?"
"Yeah?" Katherine asked.
Amy was rubbing Alan's sweet spot as she replied, while Katherine stroked the rest of his long shaft. "Well, I told you afterwards about the titfucky fun we had, and how we had to stop when Susan came by. I even told you how I sucked on him for a second or two, even though it's totally against my mom's rules right now. But what I kinda sorta forgot to mention is that even before that, before you came in, I asked Alan if I could be one of his personal cocksuckers. And... he said yes!"
Katherine raised her eyebrows. "Wow, that's interesting. That's a big step." She could feel her jealousy flaring up, but she was determined not to let it get the best of her. It helped a lot that she was getting a big thrill out of sharing her brother's cock with Amy.
Amy looked down shyly towards Alan's boner as she continued to rub it. "It's kind of... official now, and everything. I hope you don't mind, but... I mean, it makes sense. You... me... my mom... your mom... Doesn't it just seem right that the four of us should be the main ones to help him out?"
Katherine nodded. "It does." Again she searched her feelings, and she could already feel her surge of jealousy passing. It did make perfect sense, it was just that she was temporarily taken aback to hear it actually confirmed. So, after a pause to think things over, she gave Amy a smile, and said, "I suppose congratulations are in order."
"Thanks!"
Katherine added, "That said, this is a big responsibility for you. I'm not sure you have the right 'fuck toy' attitude. It's not just about pleasuring his cock at the drop of a hat, although that is a big part of it. There's a certain submissive attitude-"
Katherine was going to say more, but Amy cut in, "Let's not just talk and talk and talk. Let me SHOW you both that I'm serious! Kat, since we both have his thingy in hand, let's really drive him wild!"
Katherine relaxed, and grinned. She looked how her hand and Amy's hand were slipping and sliding on Alan's throbbing erection, and said, "That sounds like a great idea. What we're doing is good, but let's step things up a notch!"
Amy nodded, and said, "I can't suck him yet, as you both know, due to my mom's bummer rule. But Kat, you can! Why don't you bob on the top, and I'll take care of the rest?"
"Good idea!" Katherine immediately bent down, engulfed Alan's cockhead, and started to suck on it.
She moved so fast that her lips bumped into Amy's stroking fingers. But Amy quickly switched to pumping on his shaft while also fondling his balls.
Alan squirmed and clenched his teeth and his PC muscle, because the sudden increase in pleasure was almost too much to take. He had to take some heavy breaths as he tried to cope without cumming. Fuck me! Maaaan! Fuuuuck! So gooood!
Amy spoke proudly. "Now, that's what I'm talking about! Kat, check out Bo's face. He looks like he's suffering, but, like, in the best way, if you know what I mean. He's totally loving it!"
Indeed, Alan was having a great time. Katherine seemed determined to show off her oral talent to the utmost, so he was on a wild roller coaster ride of sheer pleasure. And Amy, determined not to be outdone, was stroking his shaft nearly as fast as her hand could fly.
Several minutes passed like that.
Alan had to rhythmically clench his PC muscle non-stop. He was beginning to wonder if he should call for a strategic pause when Amy asked, "What about our boobies?"
Katherine and Alan never did find out what she meant by that, because just then they heard the front door opening downstairs.