Umbreon

A habitat matching this ambience raises Comfy Level faster. Time and weather gate whether a Pokémon turns up at a habitat at all — though light overrides the clock: a night Pokémon spawns at any hour if its habitat sits somewhere dark such as a cave or underground, and a day Pokémon spawns at night if its habitat is ringed with light.

Give or place anything matching these and both friendship and Comfy Level rise much faster — a matching item lays down with a bigger sparkle. For a Pokémon with the Trade specialty, matching items are also worth 50% more on the scale.

1 Shiny stuff

77+ items

Crystal fragmentStardustGaming fridgeGaming chairGaming bedMunna bankBathtime setCleaning suppliesTabletCell phoneLaptopComputerGaming PCTelevisionWall monitorCrystal ballTabletop micStanding micGold TeethBig NuggetAuspicious ArmorClear BellGym emblem statueSpacesuitModel space shuttleBellSignpostInformation boardRaichu signFire hydrantMini generatorMushroom streetlightChic streetlightPoké Ball lightPoké Ball lampRed meteor lampOrange meteor lampYellow meteor lampGreen meteor lampBlue meteor lampIndigo meteor lampViolet meteor lampMirror ballFluorescent lightGaming lightString lightsMusic mat (low do)Music mat (Re)Music mat (Mi)Music mat (Fa)Music mat (Sol)Music mat (La)Music mat (Ti)Music mat (High do)Star PieceNuggetSilver Bottle CapGold Bottle CapMetal PowderClear AmuletRainbow FeatherSilver FeatherRed crystal fragmentDigital cameraStar closetStarry-sky bedStar-shaped DresserStar wall decorationJirachi lampMarine chestMarine closetOrnate decorative shelfSparkling jewelryDangling streetlightCursola lightDecorative clothPrism scale

2 Luxury

61+ items

Antique chestAntique closetPolygonal ShelfAntique tableChic tableLuxury tableChic chairFancy chairAntique chairLuxury chairGaming chairChic sofaAntique sofaLuxury sofaGuest-room bedAntique bedLuxury bedCute bedWall mirrorLarge mirrorAntique dresserLuxury dresserTable settingAfternoon tea setFancy penStone fireplaceDining cabinetBig NuggetAuspicious ArmorMalicious ArmorAntique clockSlender candleEerie candleFirepitChansey plantBellPoké Ball lightPoké Ball lampLuxury lampMirror ballAntique chandelierRainbow FeatherSilver FeatherJump rope trophyJewel wall decorationTreasureHide-and-sneak trophyOrnate standOrnate tableOrnate chairOrnate bedTeaware setDecorative platesOrnate decorative shelfSparkling jewelryMusic boxHarpParty ballGyarados fountainPrimarina statueLampion

3 Cute stuff

80+ items

Poké Ball ChestBerry casePolygonal ShelfCute tablePop art tableBerry chairStylish stoolCute chairPop art chairCute sofaPop art sofaPikachu sofaPop art bedBerry bedCute bedNaptime bedCute dresserWiggly mirrorRibbon cakeMunna bankBathtime setBouncy blue bathtubBoo-in-the-boxWobbuffet WobblerBerry clockRowlet clockCastform weather charmEevee dollPikachu dollClefairy dollArcanine dollDragonite dollDitto dollSubstitute dollEerie candleChansey plantInflatable boatPhoto cutout boardBerry table lampCute lampModel planetRed meteor lampOrange meteor lampYellow meteor lampGreen meteor lampBlue meteor lampIndigo meteor lampViolet meteor lampLuxury lampSeedot LampShell lampBerry hanging lampCute flowerHeart ScaleFairy FeatherFlower cushionFlowery table settingLunch boxHoppip water bottleFlower garlandFlower backpackStar closetStarry-sky bedStar-shaped DresserMoon clockStar wall decorationJirachi lampSeashell seatMarine sofaCushion bedDecorative platesWindup InkayChimecho wind chimeRunning shoesStarmie dollPrimarina statueCycle shop signCafé signGift shop signCursola light

4 Letters and words

43+ items

Office shelfLetterNotepadBookOpen BookPapersNewspaperMagazine rackMini bookcaseBookcaseTelevisionWall monitorScience experimentWhiteboardWall CalendarDecorative bookshelfHanging scrollGrubby letterGrubby notepadGrubby bookGrubby papersGrubby newspaperGravestoneArrow signMenu boardSignSignpostInformation boardRaichu signFrameWeakness PolicyMap and compassBook stackShop shelfParty ballHanging signStone signSlim information boardCycle shop signSupermarket signCafé signRestaurant signGift shop sign

5 Watching stuff

102+ items

Wall mirrorWiggly mirrorSmall vaseLeafy plantPitcher-plant potExtravagant flowersTall potted plantFlat-leaf plantTwisted potted plantLetterNotepadBookOpen BookPapersNewspaperPhoto frameWall photo frameCorkboardCD rackMagazine rackMini bookcaseBookcaseTabletCell phoneLaptopTelevisionWall monitorPinwheelsCrystal ballMicroscopeGold TeethBoo-in-the-boxWobbuffet WobblerAuspicious ArmorMalicious ArmorModel space shuttleWall CalendarDecorative bookshelfRowlet clockBerry wall decorationHanging scrollEevee dollPikachu dollClefairy dollArcanine dollDragonite dollDitto dollSubstitute dollGrubby letterGrubby notepadGrubby bookGrubby papersGrubby newspaperGrubby tabletGrubby cell phoneBonfireBlank canvasPainting (landscape)Painting (portrait)Painting (still life)Horsea fountainRaichu signPhoto cutout boardFrameTown mapTeam Rocket Wall HangingWater pillar quarterFlower garlandInflatable SudowoodoJump rope trophyJewel wall decorationTelescopeMoon clockStar wall decorationHide-and-sneak trophyDecorative Poké BallDecorative platesBook stackShop display caseOrnate decorative shelfBottled shipMetronomeDecorative Great BallDecorative Heal BallDecorative Quick BallDecorative Dive BallDecorative Net BallDecorative Lure BallWindup InkayWall plantParty ballStarmie dollGyarados fountainPrimarina statueCycle shop signSupermarket signCafé signRestaurant signGift shop signStanding frameBubble machineLampion

Flavour: bitter

11 foods

Rawst BerryPotatoSeaweedSeaweed saladSeaweed soupRecycled breadBitter hamburger steakSea grapesPopping saladPopping soupCoffee parfait smoothie

Two caveats. The game lists these five in a fixed order, but no source says the first counts for more than the fifth — the numbers are the in-game order, not a strength ranking. And the item lists are incomplete: Serebii marks them as still being filled in, so each count is a floor, not a total.