ときている

1. 1Emphatically states a trait or circumstance, often an unfavorable one, as a notable fact that leads to the speaker's conclusion.Ex. 1
2. 2Adds a further striking feature to one already mentioned, often with おまけに or その上, building up a case for a judgment.Ex. 2

It is used mainly in conversation and informal writing to highlight a trait with feeling, often exasperation, though it can also stress a favorable combination of features. The ときている clause usually gives the reason, and the main clause states the natural result or the speaker's evaluation. Unlike ときたら, which follows a noun to raise it as a topic for comment, ときている closes the clause that states the trait itself.

• ときたらN1「ときたら」 follows a noun for a person or thing and is placed at the start of the sentence to introduce the topic, which is then evaluated emotionally (mostly complaints, but admiration is possible), while 「ときている」 follows a characteristic and serves as the predicate, using it to give a reason or to stack up characteristics. The two are not interchangeable.
• だけにN2「だけに」 is stylistically neutral and stresses that the degree of the result matches the premise, can also express deeper disappointment when things turn out contrary to hopes, and requires 「な」 or 「だった」 after な-adjectives. 「ときている」 is more colloquial, carries a resigned, emotional tone, and can stack characteristics.
• くせにN3「くせに」 is adversative ("even though... still...") and carries reproach, requiring 「の」 after nouns and 「な」 after な-adjectives, while 「ときている」 is a non-adversative link that uses a characteristic as the reason for a natural result. The two are not interchangeable.
• ことだからN2「ことだから」 takes the form noun + 「のことだから」 and makes a guess based on knowing the character and habits of a familiar person or organization, often followed by 「きっと」 or 「はずだ」, while 「ときている」 follows a characteristic, carries emotion, and is more colloquial. They are generally not interchangeable.
• のなんのってN1「のなんのって」 stresses an indescribably extreme degree, mostly about personal experience, and its second half can be omitted, while 「ときている」 focuses on using a characteristic as a reason for a result or on stacking characteristics, and can also follow nouns. The two are not interchangeable.

ときたら attaches to a noun to raise a person or thing as the topic of (usually critical) comment, either at the start of a sentence or after an earlier clause (彼はよく働くが、弟ときたら…), while ときている closes the clause that states the trait; だけに and ことだから also give reasons, but だけに stresses a fitting result and ことだから infers from someone's known character. くせに reproaches a contradiction, and のなんのって exclaims an extreme degree rather than presenting a trait as a reason.