The most random places a dildo would be in Equestria (My top 10)

1. Pinkie Pie's bathroom
Why would it be there? If the girl is crazy enough to handle chaos magic, then why would a normal item like a Dildo be in her house? Goodness knows she uses an alien appendage.

2. Donut Joe's coffee shop
No way Twilight would do something that ridiculous to someone she respects. Donut Joe is a respectful stallion and thus he doesn't attract raunchy mares. Unless they are business mare's like Harshwhinney.

3. Underneath the stove in the Apple Family house
Applejack may not be able to tell a lie, but would need to if she can hide it in a place she will most likely forget.

4. The outskirts of the Everfree forest
Let's be honest here. Chances are that many mares threw their sin sticks in the Everfree for only Zecora to pick up and use for herself (Free is key). So the outskirts would be random because of Zecora and Fluttershy's house.

5. Inside of Tree Hugger
Read the location and know the pony. 'Nuff said

6. Discord's dimension
Being the lord of chaos, it would make no sense to bring sense to him. So Imma cop out here

7. The moon
Being trapped for eternity can be a lot of stress on a girl's shoulders. Lesbian or straight, relief is relief. Especially in the largest privacy space in space.
Unless Twilight was using her telescope

8. Cheerlie's favorite teacher mug
Since she teaches a bunch of 1st graders, Cheerlie can be "that" teacher. Her drawer is already filled with booze

9. Bulk Biceps locker in the gym
Under all of the prying eyes and sweat bands. A male locker room would be pretty random

10. Sweetie Belle's room
Rarity would be the type of sister to use her younger sister's bed when the wine is sweet and the chocolate is warm