It's a little sketchy, but that's okay, since I'm lazy and I actually did color.
And now, a wall of text!

• Basics (body features)
  Is a latex, animated balloon with an undefined form, though typically prefers to use a dragon as a default shape
  Characterized color-wise by a pink body, with white on the ends of limbs (where applicable)
  When possible, will physically have purple flames down the back and white 'feathery' wings, regardless of form.
  Any claws/beaks/horns are also typical latex, but with hardened tips to make them capable of puncturing things with significant effort, or particularly delicate surfaces.
  Is techically sexless, but depending on the body, may have any sex/gender.
  Any holes can accept air (or anything else really) for the purpose of inflation, but air can only be released through the nozzle, or by being popped
  Under STP, typically can be inflated to double his 'normal' size, which varies by form.

• In depth
  Is capable of reforming from being popped in moments, under normal circumstances
  When reforming, he can re-shape his own body into a form of his choosing, however he can only 'shapeshift' during reforming.
  Will only be able to reform if all 'inflated' parts are either deflated, destroyed, or otherwise relieved of stress
  Sustains his body by eating most organic materials, converting them into latex to reinforce his body with
  Excess latex is stored in an extra-demensional 'stomach', not normally accessable or corporeal, which can be 'pulled into reality' when he consumes food.
  Can still 'fly' relatively reliably, provided wind conditions are't too extreme

• Abilities
  When consuming a living being, the latex stored in his 'stomach' works as a numbing agent, as well as a potent solute, dissolving the body, but preserving the mind. The mind can then be 'infused' into a balloon created directly from his latex reserves, allowing him to 'transform' living beings into other animated balloons.
  By some arbitrary force, is significantly heavier than the mass of his latex alone, allowing him to not be quite as helpless, and also allowing for greater mobility on the ground.
  Is naturally grounded and will discharge static
  Even though he technically has no lungs, can still 'exhale' to inflate balloons. This does not decrease his internal pressure, but comes from other sources.

• Personality
  Typically follows that of the real-world counterpart, with few exceptions (given "impossible" circumstances, which can't be properly tested for)
  Tends to be friendly, though mood can vary significantly, as with most beings.
  Tries to be approachable, unless in a very bad mood (but don't be afraid to try)

• Preferences
  Enjoys attention and being played with, though he can also simply engage in conversation and be content
  Balloons > Inflatables/plushies > Flesh/other
  Prefers magic or toon physics moreso than anything overly 'realistic'
  Would take someone who actually wants to be friends over those simply seeking to play.

• Origins/Purpose/Goals
  Originally created for sexual use, but his creator rapidly lost interest, causing him to seek another purpose in life, and becoming an independant toy
  Currently seeks out use as a toy, with the goal of finding a new master to take care of him, or to find other toys to take care of himself
  Mainly takes pleasure in making others happy to the best of his ability

• Anything else?
  Feel free to ask for me to add additional information, if I can. (Some stuff I just haven't considered so I may not have a response for that)