Due to his otherworldly strength and irresistible cuteness, Kirby is able to solve issues through brute force, or charm. 

You have a +3 on Strength checks and +2 on Charisma checks.

However, his innocence and young age means he is not incredibly smart.

You have a -2 on Wisdom checks and -1 on Intelligence checks

Maturity in Kirby's species is reached upon reaching two centuries of age, and the full lifespan of this strange alien species is unknown. Kirby is still technically considered a child.

Seeking to help any in need and defend his friends, Kirby will do whatever it takes to save his allies.

Chaotic Good.

Kirby is a small creature, and so is dwarfed by most who are larger than him. Despite his small stature, he is able to take on monumental threats.

Your height is 3ft.

Kirby is a being with an unknown past, possibly having come into being when Void, the god of rebirth, came into contact with overwhelmingly positive energy, and thus Kirby is anomalous in nature. 

Your type is aberration, ooze, and celestial

As an action, if you choose to Gobble, you can attempt to draw a creature or object into your gullet and engulf them or it using your seemingly bottomless stomach. Choose a Medium or smaller creature or object within 5 feet. That creature must make a Strength + Constitution saving throw. The DC is equal to 8 + your Strength modifier + your Constitution modifier + your proficiency modifier. On a failed save, you may swallow it whole. Your gobbling gullet can only contain one creature at a time. A swallowed creature is restrained and blinded, and may repeat its save at the end of each of its turns. On a success, the creature exits prone within 5 feet of you.
As an action, if you choose to Inhale, you can choose up to 12 creatures or objects that are the same size class as you or smaller within a 15 feet cone. Those creatures in front of you must make Strength saving throws. The DC is equal to 8 + your Strength modifier + your proficiency modifier. On a failed save, the creatures in question are pulled 15 feet towards you, and you may swallow them whole. On a success, the creature exits frightened within 5 feet of you. Objects are usually eaten automatically. You may use this trait a number of times equal to your Constitution modifier before you must complete a short or long rest to use it to full capacity again.
At 1st level, you gain a sub-trait: Star Spit. At 5th level, you gain an additional subtrait: Swallow. At 20th level, you gain an additional subtrait: Mouthful Mode.

Star Spit. While you have a creature or object within your gullet you can attempt to fire it out of your mouth as an action. When fired, you deal 3d10 + Constitution force damage to all creatures and objects that were in your mouth, which increases by 1d4 for every 2 objects and/or creatures added after the first. Anything hit with this projectile takes the same damage as the victims in the gullet. If you are using this projectile with one victim in your gullet, it hits the opponent and bursts on contact. If you are using this projectile with 2 or more victims in your gullet, it can pierce through multiple targets and only bursts on contact when hitting non-destructible surfaces, like sturdy walls. At 10th level, you gain an improvement: When fired, you deal 6d10 + Constitution force damage to all creatures and objects that were in your mouth, which increases by 1d4 for every object and/or creature added after the first.

Swallow. While you have a creature(s) within your gullet you can attempt to copy one of its abilities as an action, expelling the creature when you do so as per your Inhale trait. When  using Swallow, roll a D6 to reveal what benefits you gain from the following:

1. You learn one of the cantrips it knows. Charisma is your spellcasting ability for it.
2. You gain one of the natural weapon attacks it has, except all damage dice for the new attack are changed to d4s and the attack always uses your Strength score.
3. You gain proficiency in one of the weapons it is proficient in.
4. You gain its racial ability score increases.
5. You gain all the racial traits and abilities, however they are halved in strength
6. You gain their class traits, abilities, proficiencies, and their spell slots and spells if they are a magic user, (downgraded if you are a lower level and equal to their level if you are a higher or equal level).

You regain use of this trait once you complete a short or long rest, at the cost of losing the gained ability. You can choose to keep the "Copy Ability" if you do not want to regain the use of Swallow.

Mouthful Mode. While you have an object that is one size larger or more than you within your gullet you can utilize the object's size, shape, and/or function to manipulate to your own desire; 2D shapes can interact with the properties of your elastic body, 3D Shapes can grant you weight and properties relating to their shape, containers can spit out their contents, and vehicles can be driven. However, you cannot fly while an object is in your mouth, as per usual.

Lighter than Air. You are oddly buoyant. As an action, you can use your Inhale trait; you holding your breath caused you to swell and become buoyant, causing you to fall slower or float on top of liquids heavier than air. To use this trait, your gullet must be empty, and you cannot be wearing heavy armor and you must use your action each round to maintain this effect. At 10th level, you gain a sub-trait: Airborne.

Airborne. Rather than a form of wings, you inhale air into your hollow body, and float around like a balloon, and your Constitution score increases by an additional 1.

At the 17th level, you gain the ability to wear heavy armor while flying.

Kirby doesn't know many words other than the greeting "Hai", the word "Poyo" which he says commonly, and his name "Kirby". He is able to pick up on words in certain languages, with "Common" being the easiest to pick up on, however he does not know the meaning of these words and so has difficulty communicating verbally.

You have a situational disadvantage in scenarios requiring verbal response.

Kirby is incredibly soft and squishy, and so is easily able to fit into tight spaces.

You can fit into spaces that would normally require you to be tiny.