Type: Dark/Steel
Ability: Guard Armor/Sturdy
Hp:85
Atk:120
Def:100
SpAtk:80
SpDef:80
Spd:75
There is no escaping the superior maid. No really I'm not even kidding, with pursuit, sculpture, priority, both physical and special coverage options, and even supporting moves to shove pointy objects into your waifu's feet there is no place to run or hide, and between her 120 base attack and 85/100/80 bulk she can win most straight up fights with ease. Just take your swords to the face and move on to...Sets.
Set: Hunt You DownYumeko @ Mistress Outfit/Lum Berry/Leftovers
Ability: Guard Armor
Evs: Hp 200/Atk 252/Spd 56
Adamant nature (+Atk,-SpAtk)
-Pursuit
-Sculpture
-Blade Flash
-Spikes/Poison Jab/Superpower
With the given EV's Yumeko can out speed base 80's with up to 16 points of investment along with 168 speed TToyohime and APatchouli while maximizing her bulk and her ability to hurt things in the everything. Yumeko boasts the strongest pursuit in game, allowing her to clean OHKO or cripple most mons that do not resist it or pack hefty physical bulk on the switch making her one of the few truly reliable counters to omg nuclear attackers suck as Attack Flandre or Attack Patchouli. Blade flash picks off faster threats while sculpture ends wish/Detect shenanigans. The last spot can be used for either spikes to abuse Yumeko's decent bulk or a coverage move to hit annoying hearts and waters.
Set: Swords EverywhereYumeko @ Lum Berry/Maid Outfit
Ability: Guard Armor
Evs: Hp 8/Atk 252/ Spd 248 Or Hp 164/Atk 252/Spd 92
Jolly nature (+Spd,-SpAtk) Or Adamant nature (+Atk,-SpAtk)
-Swords Dance
-Outrage
-Sculpture/Blade Flash
-Killing Bite/Superpower
With her fantastic bulk and amazing typing Yumeko is quite capable of dancing with pointy things however her low speed is an issue making her a huge fan of baton passers. With a jolly 8/252/248 spread Yumeko out speeds + speed 135 base mons at +1 while an adamant 164/252/92 spread allows her to outrun +speed base 140's at +2. Outrage and sculpture provides a potent STAB combination while blade flash offers priority. Killing bite is just here to nail ghosts while superpower is for big boy Tensoku.
Set: Predictions Bitch, PredictionsYumeko @ Special Bloomers
Ability: Guard Armor
Evs: Hp 200/Atk 252/Spd 52
Adamant nature (+Atk,-SpAtk)
-Pursuit
-Blade Flash
-Poison Jab
-Superpower
Banded Pursuit is stupidly powerful allowing for a clean OHKO on -1 AFlandre and ARemilia on the switch through resistance. Blade flash is blade flash and allows Yumeko to easily pick off threatening sweepers while poison jab and superpower provide powerful coverage options.
Support: Yumeko likes having team mates that can take heart, fire, faith and earth hits aimed her way making Luize a near ideal companion thanks to her combination of typing, ability, and even heal bell + wish support. SD Yumeko loves speed boosts and can come in on many of SYamame, Lily Black, and THatate's weaknesses.
Options: Yumeko has access to taunt to either set up SD's or annoy walls however the 4MSS is strong with her so its pretty situational. You can also do plain silly things like running a -Def/SpDef nature alongside thunder to nail Kisume and HEirin if your Agastya. Its also worth noting that her sets are pretty much mix and match depending on the needs of your team.
Counters: While almost nothing enjoys swapping out of Yumeko bulky waters and fires love to swap in on her, HEirin, TToyohime, DMokou, Tensoku and Kisume fear almost nothing Yumeko can do while Rin continues to be a hardcore stop to any and every steel type not packing waterfall.