A very pleasurable sensation wakes you up the next morning. When you get your bearings you realize you're laying in bed in your wife's arms. Two of her black tentacles have your legs pinned in a spread-eagle position while a third tentacle is fondling your balls and a fourth is slowly jerking you off. What a pleasant surprise to wake up to.
"Hi honey" your wife whispers in your ear. "I thought I'd help you along."
"Thanks" is all you can think to say. "I'm almost..." You shudder as she adjusts her technique and let out an involuntary moan before climaxing, spraying your seed off the end of the bed.
"I should clean that up" you say.
"Later" she says. "How do you feel? Would like you like to have some more fun?"
"Maybe after breakfast. You're insatiable."
"Orgasms help the change along. I found that out yesterday while you were at work."
"Is that how I left you with legs and came back to find you without any?"
"Mmmmhmmm. Now that I know how to speed the change along I think we can have you transformed by tonight."
"Transformed? What are you talking about?"
You feel a tentacle take your hand and guide it down to your hips where you find a fleshy nub. You quickly feel around your waist with both hands and sure enough there are eight of them. Just like your wife's transformation started. You're infected and beginning to change into cecaelia too. How long before your legs are replaced with octopus tentacles? Can you stop it? Do you want to?