All Islamic jurisprudence have been categorised in to five section.
1-Wajib (Obligatory) you have to do it if don’t do will be punished.
2-Haram (Restricted) don’t do it if you do it will be punished.
3-Mustahab ( recommended to do it if you do it will be rewarded and if you don’t do it you will not be punished.
4-Makrooh ( recommended to not do it but if don’t do will be rewarded and if you do it you will not be punished.
5-Mubah ( doesn’t matter either you do it or don’t do that).
Now if anyone has not used any thing in his tattoos which is against Islamic Shariya and ethics then there is no issue it it even it would not considered as a Makrooh.
But we should avoid having such western culture which has no value and sense.