Try to swing

Already a few more tentacles are reaching out for you, touching your skin with flattened tips, like a dozen licking tongues. They prove to be quite distracting but fortunately the blob seems to be focusing on the taste of the salt on your skin because it doesn't notice how you swing your legs back and forth.

You build up speed and soon you are swinging too and fro, hanging from the thick vine around your waist. You can feel all the tentacles stretch out more and more as you swing faster, and as they stretch they are drawn thinner, like silly putty stretched too far.

At exactly the right moment, at the height of your swinging motion when you are heading towards the bathtub, you pull with all your might at the tentacles around your arms. Just as you had hoped they had become stretched too far and snap! Immediately you grab the one around your waist and pull, snapping that as well, which lets you fly through the air and land in your bathtub with a heavy bang as your head hit the tiled wall behind it.

You see stars and comets and interesting fireworks, and for a while you do nothing but lie in the tub, your legs hanging over the side, and breathe greedily. The monster in the ceiling seems to be temporarily dazed as well after losing a good chunk of its body mass, most of which is now slowly forming a sticky pool of black goo in the tub beneath you.

You are free! Now, you only have one chance so you should decide your next move carefully. You must make sure that the blob can't find you again, or at least not catch you, until you can make it out of the bathroom.